Australian Journal of Crop Science   AJCS

Effect of the organic matter from crop residues on the structuration of an Oxisol, at semi-arid region

Elioneide Jandira de Sales Pereira, Marineide Jussara Diniz, Joaquim Odilon Pereira*, Priscila Pascali da Costa Bandeira, Ana Clara Carvalho Costa, Suedemio de Lima Silva, Rafael Oliveira Batista, Paulo César Ferreira Linhares, Roberto Pequeno de Sousa, Janilson Pinheiro de Assis, Walter Martins Rodrigues, Antonio Ronaldo Gomes Garcia, Rutilene Rodrigues da Cunha, Kadidja Meyre Bessa Simão

Universidade Federal Rural do Semi-Árido, 59625-900, Mossoró - RN, Brasil
Departamento de Engenharia e Ciências Ambientais, Departamento de Ciências Agronomicas e Florestais, Brasil
Departamento de Ciencias Naturais, Matemática e Estatistica, Brasil

Abstract
Crop residues can either be incorporated into the soil or left on the soil surface as a mulch producing soil organic matter in different quantities, having many potential benefits such as reducing soil compaction caused by passage of agricultural machines. The aim of this study is to evaluate the effect of crop residues such as maize and bean straw on the dynamic properties of a sandy soil incorporated in the laboratory condition. The experiment was carried out in laboratory. Air-dried maize (Zea mays L.) and cowpea (Vigna Unguiculata L. Walp) straw with an average size of 35 mm were incorporated into the soil in proportions of 2%, 4%, 6% and 8% in trays. Sample of each soil was collected to determine the organic matter after 120 days in wet conditions. An isolated design was carried out for each soil from maize and bean straw, consisting of two soil densities (1.2 and 1.4 g/cm3), 4 carbon contents and 4 water contents from tensions of 20, 40, 60 and 80 kPa (2x4x4) with 3 repetitions. The soil compression curves of the soil samples were determined adjusted in cylinders with 70 mm diameter and 24 mm in height using the oedometric test. The structural voids index as a function of applied pressure, as well as the soil compression index and pre-compression stresses as a function of water content and carbon content were evaluated using linear regression models with coefficient of determination at 95% confidence. The soil compression index showed a strong positive correlation with organic matter (carbon) derived from bean (r = 0.905) and maize straw (r = 0.787) at 95% confidence. The soil density was 1.2 g cm-3, which was explained by a simple linear regression model.

Pages 107-117 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3445
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Biometrics and physiological parameters of sour passion fruit seedlings produced on organic substrates

Luana Nascimento da Silva, Lucas Kennedy Silva Lima, Idália Souza dos Santos, Sidnara Ribeiro Sampaio, Mauricio Antônio Coelho Filho, Onildo Nunes de Jesus*

Federal University of Recôncavo da Bahia, Cruz das Almas, Bahia, Brazil
CNPq, Embrapa Cassava and Fruit, Cruz das Almas, BA, Bahia, Brazil
Program in Plant Genetic Resources, Federal University of Recôncavo da Bahia, Cruz das Almas, Bahia, Brazil
Rural Education, Federal University of Recôncavo da Bahia, Amargosa, Bahia, Brazil
Embrapa Cassava and Fruit

Abstract
The organic fruit market has expanded considerably in recent years, but for the establishment of more productive organic orchards, several aspects need to be studied, starting with obtaining good quality seedlings. In this work, different formulations of organic substrates were evaluated to select the one that provides greater vigor to Passiflora edulis Sims seedlings. The study was conducted under anti-aphid screen conditions in two regions of Bahia (Recôncavo da Bahia, Chapada Diamantina), using a completely randomized design. The substrates were prepared using different proportions of coconut fiber, vermiculite, bovine manure and bokashi. At 60 days after sowing, germination vigor, gas exchange and growth parameters were evaluated. The data were submitted to principal component analysis and the groups formed were represented by box plots and compared by the Tukey test. Three groups were formed from PCA for the seedlings produced in both regions and the joint analysis, considering the two environments. In Chapada Diamantina, the seedlings produced in group 1, corresponding to 40% of the substrates tested, stood out for their root characteristics. In Recôncavo da Bahia, the seedlings showed low variation between the treatments G1C and G2C (80% substrates), compared to the G3C seedlings. The best performance was observed in the seedlings produced in Chapada Diamantina, but the use of coconut fiber and soil (CfSB), vermiculite and soil (SVB), both with 5% bokashi, produced excellent seedlings in both regions, so it is recommended for the organic production of P. edulis.

Pages 118-129 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.23.17.02.p3549
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Activity of Nerium oleander leaf extract on the larvae of Crocidolomia binotalis Zell.

Moh. Hibban Toana*, Burhanuddin Haji Nasir, Fitriah Balosi, Reza Anugrah

Department of Agriculture, Agriculture Faculty of Tadulako University, Palu, Indonesia, 94118

Abstract
The active compound of Nerium oleander L. leaf extract is toxic to insect larvae. It is used to control pests but information on the activity of N. oleander leaf extract was not yet known in detail. This research aimed to determine mortality, lethal concentration (LC50), feeding inhibition, larval and pupal fitness weights and imago morphological perfection of Crocidolomia binotalis Zell. The research was done at the Laboratory of Pests and Plant Diseases, Faculty of Agriculture, Tadulako University from May 2021 to October 2021. This research used a completely randomized design with five treatments and four replications. Each treatment used 20 tails sample of third instar C. binotalis larvae from East Lore Sub-district, Poso Regency. Concentrations for the treatment of N. oleander leaf extract were as follows: P0 = 0%, P1 = 1.25%, P2 = 2.5%, P3 = 5%, and P4 = 10%. The results show that the concentrations of N. oleander leaf extract that were effective in causing mortality of C. binotalis larvae, were from 1.25% to 2.5%. The LC50 concentration of N. oleander leaf extract, which killed 50% of C. binotalis larvae, was 1.915% (0.01915ml/ml), with a minimum concentration of 1.425% (0.01425ml/ml) and a maximum concentration of 2.375% (0.02375ml/ml). The higher the concentration of N. oleander leaf extract, the higher the feeding inhibition, causing the decrease in the feeding of C. binotalis larvae. In addition, the fitness weights of C. binotalis larvae and pupae also decreased, so that fewer larvae developed into imago (adult individuals). A 10% concentration of N. oleander leaf extract caused abnormal (rudimentary) morphological forms of C. binotalis imago.

Pages 130-137 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3648
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Factors influencing success of the cocoa (Theobroma cacao) product certification program in tropical areas

Made Antara*, Arifuddin Lamusa, Effendy, Muhardi, Andarias Pagalla

Department of Agriculture Economics, Agriculture Faculty of Tadulako University, Palu 94118, Indonesia
Department of Agrotechnology, Agriculture Faculty of Tadulako University, Palu 94118, Indonesia
Master of Agribusiness Study Program, Agriculture Faculty of Tadulako University, Palu 94118, Indonesia

Abstract
Cocoa is one of the leading national commodities after rubber, palm oil, coffee, and tea. Cocoa has a significant impact on the economy in Central Sulawesi, especially in terms of creating new jobs and sources of income for farmers. The decline in cocoa productivity and quality will affect farmers' income in rural areas. In recent years, several cocoa industry and cocoa trading companies such as Mars Inc., Mondelez International, Cargill, Barry Callebout, and JB Cocoa have begun to focus on developing product certification programs for selling by allocating several CSR (Corporate Social Responsibility) funds to conduct training and technical assistance in cultivation (pruning, fertilizing, frequent harvesting and sanitation) for cocoa. Therefore, several socializing requirements or compliance standards must be met by farmers who are members of the certification program, namely the CoC (Code of Conduct) established by certification bodies such as UTZ. The purpose of this study was to analyze the factors that influence the success of the cocoa certification program in Central Sulawesi. 80 families were chosen as number of samples. A logistic regression model was used to answer the research objectives. The results showed that the land area, farmer's age, level/year of farmer's education had very small influence on the success of the certification program in Central Sulawesi. The linkage of debt with traders considerably influences the success of product certification programs. Cocoa production, income factors, traders' domicile, and merchant service patterns have a significant influence on the success of the certification program.

Pages 138-145 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3689
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Allelopathic effects of tamarind husk, lemongrass and citronella residues to suppress emergence and early growth of some weeds

Siriphan Sukkhaeng*, Somnuk Promdang, Atinuch Saejiw, Piyanan Thanomchat, Srisom Suwanwong

Central Laboratory and Greenhouse Complex, Research and Academic Service Center, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen campus, 73140, Thailand
Scientific Equipment and Research Division, Kasetsart University Research and Development Institute (KURDI), Kasetsart University, Bangkok 10900, Thailand
Department of Botany, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand

Abstract
The allelopathic effects were evaluated of water extracts from tamarind (Tamarindus indica L.) husk and from lemongrass (Cymbopogon citratus Stapf.) or citronella (Cymbopogon nardus Rendle.) leaves on 2 test plants: ruzi grass (Brachiaria ruziziensis Germ. & C.M. Evrard) and popping pod (Ruellia tuberosa L.). In the laboratory, the seeds were subjected to the different extracts at concentrations of 0, 1.25, 2.5, 5 and 10 % (w/v). The number of germinated seeds was counted daily for 6 days. The shoot/root length was measured 5 days after sowing (DAS). The results showed that the aqueous extract of tamarind husk did not inhibit the germination of either ruzi grass or popping pod. The lemongrass and citronella extracts had higher inhibition effects at high concentrations and clearly delayed seed germination at 10 % (w/v). With the seedling growth bioassays of the 3 extracts, only the citronella extract at the highest concentration had any effect on the shoot/root lengths of ruzi grass. Popping pod was susceptible to all 3 extracts, especially the popping pod roots treated with lemongrass and citronella extracts. The lemongrass and citronella extracts caused cell death and induced lipid peroxidation in both plants. Therefore, the primary action of these extracts on seedling growth inhibition might have been related to the loss of cell viability and triggering lipid peroxidation in affected tissues. The residue incorporation bioassay determined the effects of residue mixed in soil at concentrations of 0, 2.5, 5 and 10 % (w/w) on the growth of ruzi grass and popping pod at 30 DAS. Both plants showed an adverse effect than for the control, based on reduced leaf numbers and greater chlorosis, especially with soil incorporation of the lemongrass and citronella residues at 10 % (w/w). Mixing soil with lemongrass and citronella leaves at 2.5 % (w/w) and above resulted in reductions in the shoot/root lengths and shoot/root biomass values. Catechin, gentisic acid, syringic acids, p-coumaric acid and ferulic acid were the dominant allelochemicals found in the lemongrass and citronella residues.

Pages 146-154 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.23.17.02.p3718
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Role of metabolization and conjugation of herbicides in tolerance of white oats to 4-Hydroxyphenylpyruvate Dioxygenase (HPPD) enzyme inhibitors

Gesieli Priscila Buba, Clovis Arruda Souza*, Camila Cigel, Matheus Santin Padilha, Antônio Mendes Oliveira-Neto

Universidade do Estado de Santa Catarina, Lages - SC, Brazil

Abstract
The success of chemical control is dependent on crop tolerance to herbicides and their efficiency in controlling weeds. Thus, knowledge of the tolerance level of cultivated plants and the tolerance mechanism involved is crucial for safe herbicide use. The objective of this study was to evaluate the effect of metabolization (malathion) and conjugation (NDB-Cl) inhibitors on the tolerance of white oats to the herbicides mesotrione and tembotrione. The experiment was carried out under field conditions in the 2021 crop, in an RBD, with nine treatments, namely: T0- control (no application); T1- malathion; T2- NBD-Cl; T3- mesotrione; T4- mesotrione+malathion; T5- mesotrione+NBD-Cl; T6- tembotrione; T7- tembotrione+malathion and T8- tembotrione+NBD-Cl. The plant characteristics were evaluated for plant intoxication, SPAD index, levels of chlorophyll a, b and total carotenoids, yield components, yield and industrial grain quality. Symptoms of intoxication in oat plants started at 7 DAA and increased up to 14 DAA in treatments containing mesotrione or tembotrione. Plant recovery started at 21 DAA, and it was intensified at 28 DAA. Intoxication levels were not affected by the addition of the metabolization inhibitors malathion (43.1%) and NDB-Cl (36.2%). There was no change in other variables tested under the control treatment . Based on these findings, it can be concluded that there was no change in the level of tolerance of white oats to the herbicides mesotrione or tembotrione after application of malathion and NDB-Cl. This outcome suggests that metabolization or conjugation are not the main mechanisms that make white oat tolerant to HPPD enzyme inhibitors.

Pages 155-164 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.23.17.02.p3732
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Seed treatment with magnesium nanoparticles alters phenology and increases grain yield and mineral content in maize

Cristiane Segatto, Clovis Arruda Souza*, Márcio Antônio Fiori, Cristiano Reschke Lajús, Luciano Luiz Silva, Humberto Gracher Riella

Santa Catarina State University, Agronomy Department, Crop Plant Laboratory, Lages, Santa Catarina, Brazil
Universidade Comunitária da Região de Chapecó, Chapecó, Santa Catarina, Brazil
Federal University of Santa Catarina, Faculty of Chemical Engineering, Florianópolis, Santa Catarina, Brazil

Abstract
Magnesium is an essential macronutrient for maize crop and its efficiency of absorption and utilization by plants can be improved when used in the form of nanoparticles. The objective of this work was to evaluate the efficiency of different sources of magnesium oxide via seed treatment in the agronomic performance of maize. The experiments were carried out under field conditions in three locations in the state of Santa Catarina, Brazil. In all experiments, the P4285HYR-hybrid maize seeds were used, with three sources of magnesium: MgO-NPs, MgO@C-NPs and Mg(NO3)2; and six concentrations: 0 (control); 37.5, 75, 150, 300 and 600 mg L-1. The following variables were analyzed: SPAD reading, NDVI, plant height, ear insertion height, number of grains per ear, grain moisture, thousand grain weight, yield and quantification of Mg, Ca, P and K in the grains. The results showed that the seed treatment with magnesium oxide alters the V4 and V5 phenological stages (fourth and fifth developed leaves), shortening the plant life cycle by four to five days (P<0.05). All applied concentrations increased maize grain yield, with greater improvement in the order of 38% with 150 mg L-1 of MgO-NPs and 57% with 300 of MgO@C-NPs in comparison to control, respectively. The use of 75 and 150 mg L-1 of magnesium nitrate increased grain yield by only 2.3% and 6.6%, respectively, when compared to the control. The P>K>Mg>Ca levels in the harvested grains were increased by seeds treated with Mg. The results were significantly influenced by the nanoparticles, when comparing with conventional Mg nitrate or with the control. Therefore, it was concluded that the use of magnesium nanoparticles via seed treatment is a viable strategy to increase maize grain yield.

Pages 165-178 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3734
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Spatial variability of wheat yield using the gaussian spatial linear model

Miguel Angel Uribe-Opazo*, Gustavo Henrique Dalposso, Manuel Galea, Jerry Adriani Johann, Fernanda De Bastiani, Emma Norma Cambillo Moyano, Denise Maria Grzegozewski

CCET/PGEAGRI, Western Paraná State University – (UNIOESTE), Cascavel, Paraná, Brazil
PPGBio, Federal University of Technology – Paraná (UTFPR), Toledo, Paraná, Brazil
Department of Statistics, Pontifical Catholic University of Chile – (UC), Santiago, Chile
Department of Statistics, Federal University of Pernambuco – (UFPE), Recife, Pernambuco, Brazil
Department of Statistics, National University of San Marcos – (UNMSM), Lima, Perú

Abstract
Wheat production has grown over the years and is one of the most important grain food sources for humans. This work analyzed the yield of two varieties of wheat planted in a regular sampling grid in an experimental area in the south of Brazil, using some explanatory variables. For the study of the spatial variability of wheat yield of the COODETEC 101 (CD101) and COODETEC 103 (CD103) varieties, which were cultivated by the farmer in an area of 22.62 ha, 84 samples were defined considering a regular grid of 50 x 50 m. In the sampled sites, the following explanatory variables were collected: average plant height in 60 days - avheight 60 (cm), the average number of tillers in 60 days - avtillers60 (cm), spike length in 120 days - splength (cm) and the wheat variety considered as a dummy variable (CD101 = 0 and CD103= 1). The wheat yield was analyzed using gaussian spatial linear models with different geostatistical models for the parametric form of the variance-covariance matrix. The significance of the parameters to select the explanatory variables were determined by the likelihood ratio test, and also a hypothesis test was presented to confirm that a model that deal with the spatial dependence was required by the data. To assess the global and local influence of some observations, diagnostics techniques based on Cook’s approach were considered.
The disregard of potentially influential observations caused changes in the parameters estimates that define the spatial dependence structure, and consequently then in the profitability in sectors of the wheat yield maps. The study of statistical inference and diagnostics on spatial data should be part of all geostatistical analysis.

Pages 179-189 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3742
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Identification of waxy genotype in sorghum genetic resources using waxy gene-based markers and iodine staining methods

Lizza Fauziah Suroya, Desta Wirnas*, Trikoesoemaningtyas, Reflinur

Plant Breeding and Biotechnology Study Program, Graduate School, IPB University, Bogor 16680, West Java, Indonesia
Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University, Bogor 16680, West Java, Indonesia
Research Center for Genetic Engineering, Research Organization for Life Sciences and Environment, National Research and Innovation Agency, Cibinong, Bogor 16911, West Java, Indonesia

Abstract
Sorghum is widely recognized as a versatile crop with significant value in the production of food and energy. Sorghum with waxy trait (low amylose) is more palatable to the food industries and more appealing to consumers than nonwaxy variety. However, waxy sorghum has not yet been introduced to Indonesia, making it difficult to use sorghum to support the government of Indonesia's initiative to diversify the country's main foods. This study aimed at identify the waxy traits in a set of sorghum germplasm collected in Indonesia using waxy gene-based markers and iodine staining screening approaches. A total of 48 (27 introduced and 21 local) sorghum accessions collected in the IAARD gene bank along with 4 national sorghum varieties, which were subjected to both molecular analysis and iodine staining assay. The presence of waxy allele in the sorghum gene bank collection was identified using DNA markers associated with two waxy alleles (wxa and wxc). Iodine staining assay performed in the present study was applied to verify the waxy phenotype in sorghum grain and waxy genotypes in sorghum pollen. Based on molecular analysis and pollen staining, five local sorghum accessions were classified as heterowaxy sorghum. These accessions showed reddish-brown color in their endosperm after treated by iodine staining which confirmed them as waxy phenotype. These findings would be beneficial for further improvement of grain quality in sorghum breeding programs.

Pages 190-197 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3784
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Agronomic biofortification with zinc in hydroponically cultivated lettuce

Bianca Machado de Lima*, Caio Salvador Noboa, Felipe Marques de Lima, Simone da Costa Mello, Luis Felipe Villani Purquerio, Fernando Cesar Sala

Institute Agronomic of Campinas, Campinas, SP, Brazil
University Federal of São Carlos, Araras, SP, Brazil
School of Agriculture "Luiz de Queiroz”, Piracicaba, SP, Brazil

Abstract
Lettuce is the most cultivated leafy vegetable in hydroponic systems. The biofortification of lettuce with zinc (Zn) can contribute to relieving nutritional deficiencies in socially vulnerable populations. Biofortification is affordable, easy and fast, even in urban areas. Our objective was to evaluate the effect of Zn concentration in nutrient solutions on the production and agronomic biofortification of lettuce cultivars. The experimental design was completely randomized, in a split-plot design, with four replicates. We tested Zn concentrations of 0.3, 1.0, 1.7 and 2.4 mg L-1 in the hydroponic solution and the cultivars 'Vanda' and 'Saladela'. We evaluated plant diameter, number of leaves, fresh and dry mass of the aerial part and root, a chlorophyll index, Zn content and the accumulation of Zn in leaves and roots. 'Vanda' lettuce had the largest diameter, and 'Saladela' lettuce had the most leaves. The fresh mass of the aerial part was higher in 'Vanda' lettuce. For a Zn concentration of 2.4 mg L-1, the Zn contents of the leaves and roots were 733.3 and 2441 mg kg-1 and the accumulations of Zn in the leaves and roots were 931.66 and 4890 mg plant-1, respectively. Zn content and accumulation were higher in 'Saladela' lettuce. FM, DM did not decrease with increasing Zn concentration in the nutrient solution. Agronomically biofortifying the lettuce produced hydroponically using the nutrient film technique was thus possible.

Pages 198-205 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3786
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Analysis of NPK nutrient content and the nutrient balance of cassava for sustainable high productivity in Ultisols soil

Suwarto, Ridwan Diaguna, Edi Santosa, Arief Hartono, Gatot Pramuhadi, Nunung Nuryantono

Departement of Agronomy and Horticulture, Faculty of Agriculture, IPB University, Bogor, 16680, Indonesia.
Department of Soil Science and Land Resources, Faculty of Agriculture, IPB University, Bogor 16680, Indonesia.
Department of Mechanical and Biosystem Engineering, Faculty of Agricultural Engineering and Technology, IPB University, Bogor 16680, Indonesia.
Department of Economics, Faculty of Economics and Management, IPB University, Bogor 16680, Indonesia

Abstract
The decline in soil fertility and productivity has been a problem in cassava cultivation. The plant biomass transported from cassava fields at harvest losses several nutrients. This study aimed to determine the nitrogen (N), phosphorous (P), and potassium (K) nutrient content of plant parts of cassava and the nutrient balance. The cassava varieties of UK1 Agritan, Malang 4, Barokah, UJ-5, and Mangu were grown in 3 replications using a completely randomized design. Two harvesting methods, the farmer’s harvest method (FHM) and the harvest method introduced (HMI) were applied. The FHM transported all tuber and other plant parts biomass, and the HMI transported all tuber and 60% of the stem from the cassava field. Each replication was one row of plants 20 m long and a spacing of 1 m. The cassava fertilized at 169 kg N, 84 kg P, and 170 kg K per hectare in grooves around the plant. The leaves of the five varieties contain higher N, P, and K than the petiole, stem, and tuber. At harvest, the N and P nutrients were mainly transported from the leaves, and K nutrients from the tubers. For a yield of 40 tons ha-1 fresh tubers, the FMI resulted in an average nutrient balance for N (-222 kg ha-1) and K (-103 kg ha-1) and P (48 kg ha-1), the HMI resulted in an average nutrient balance of 305 kg N, 56 kg P, and 82 kg K per hectare. The HMI is recommended for sustainable soil fertility and high productivity of the cassava field.

Pages 206-214 | Full Text PDF| 10.21475/ajcs.23.17.02.p3796
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Plantlet quality of Coffea canephora propagated vegetatively from different stem cutting types

Cleidson Alves da Silva, Millena Monteiro dos Santos, Matheus André Partelli Stocco, Gladyston Rodrigues Carvalho, Henrique Duarte Vieira, Fábio Luiz Partelli*

Programa de Pós-Graduação em Fitotecnia, Universidade Federal de Lavras, Lavras, Minas Gerais, Brazil
Programa de Pós-Graduação em Agricultura Tropical, Universidade Federal do Espírito Santo, São Mateus, Espírito Santo, Brazil
Instituição de Ensino Superior Multivix, Nova Venécia, Espírito Santo, Brazil
Empresa de Pesquisa Agropecuária de Minas Gerais, Epamig Sul Lavras, Lavras, Minas Gerais, Brazil
Centro de Ciências e Tecnologias Agropecuárias, Universidade Estadual Norte Fluminense-Darcy Ribeiro, Campos dos Goytacazes, Rio de Janeiro, Brazil
Departamento de Ciências Agrárias e Biológicas, Universidade Federal do Espírito Santo, São Mateus, Espírito Santo, Brazil

Abstract
Coffea canephora trees are grown from cutting-derived plantlets. Thus, the objective was to evaluate the performance of C. canephora plantlets propagated by stem cuttings with different models. The experiment to assess the plantlet performance in the nursery stage was arranged in a completely randomized design and that of the early field development in randomized blocks. The four evaluated treatments consisted of different cutting types with different number of nodes, number of leaves and presence or absence of the apical bud. In the nursery phase, characteristics related to the shoot and root development of the plantlets and the shoot characteristics of the early field development were evaluated. The data were subjected to analysis of variance by the F test (p≤0.05) and the means compared by the Tukey test at 5% probability. The hierarchical clustering method UPGMA was applied to detect the similarity between treatments considering all studied variables. The plantlets grown in the treatments with cuttings with two leaf pairs, with and without the apical bud, and the treatment with three leaf pairs with the apical bud were superior to those grown by the conventional method in the nursery phase. The plantlets grown from cuttings with two leaf pairs and the presence of the apical bud stimulated the early field development of coffee trees. Thus, it is suggested not to cut the apical bud on the cutting, since it would bring better seedling quality and without additional costs for its production.

Pages 215-222 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3797
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A new soil-plant image segmentation approach using K-means applied to experimental plots

Danilo Pereira Barbosa, Cristiano Ferreira Oliveira, Luiz Alexandre Peternelli*

Instituto Federal Goiano, Brazil
Department of Statistics, Universidade Federal de Vicosa, Viçosa, MG, 36570-900, Brazil

Abstract
The image segmentation procedure is fundamental in the phenotyping of plant images. Supervised algorithms have been used for pixel soil plant segmentation. Recent research has used the K-means algorithm to evaluate the segmentation of agronomic images in different crops with different databases. The algorithm has shown good performance in the pixel clustering process despite not being able to classify them directly. The present research intends to propose using the K-means algorithm in image segmentation and pixel classification in sugarcane images. 37,430-pixel samples referring to soil and vegetation were manually extracted from some images. This information was used to train and evaluate supervised models. The model with the best performance was considered the "standard" model. A rule that can serve as empirical support to interpret the clusters formed by K-means by assigning a label to each pixel was proposed. Then K-means was used to segment all images and classify the pixels. The vegetation index was used as features and the standard model classification was used as a true label. The measures recall, F1Score, precision, and accuracy were used as a performance measure of K-means, and the mask of each produced to compare the final result of the two approaches, highlighting the vegetation. Using K-means provided better-defined edges than Logistic Regression (standard model) and considerably distinguished the occurrence of soil between the leaves, with precision ranging from 0.77 to 0.92. These results expressed the importance of vegetation index to the clusterization process and showed that K-means ally to an interpretation clusters rule, which could be used to classify pixels in images.

Pages 223-232 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3802
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Responses of modern and local Thai rice varieties to the aerobic soil

Supansa Chinaworn*, Rattikarn Sennoi, Thanidchaya Puthmee, Pramote Pornsuriya

Department of Plant Production Technology, Faculty of Agriculture and Natural resources, Rajamangala University of Technology Tawan-Ok, Bangpra Campus, Bangpra, Sriracha, Chonburi province 20110, Thailand

Abstract
This study evaluated responses of modern and local Thai rices to find varieties that are suitable for growing in water-limited areas under aerobic and anaerobic soils. Nine rice varieties and two soil water conditions were arranged as a factorial design in a completely random design (CRD) with three replications. The agronomic traits that were measured consisted of 50% flowering date, plant height, yield components, harvest index (HI), and grain yield plant-1. Growing rice under aerobic soil significantly reduced plant height, yield components and grain yield, compared with anaerobic soil. However, the reduction differed depending on the variety. The modern rice varieties tend to be more adapted to the aerobic soils, compared to local. Modern rice varieties, RD29, RD49, and RD57, and a local rice variety, Chiang Phatthalung, tend to be better adapted under aerobic soil. These were clearly indicated by the smallest reduction in some agronomic traits under aerobic compared to anaerobic conditions. The plant height of RD57 was 107.93/ 104.53 cm in anaerobic and aerobic, respectively. The tiller number plant -1 in RD57 was 15.2/ 8.8; panicle number plant -1 in RD57 was 14.67/8.7 and in RD29 12.6/7.7; spikelet number plant -1 in RD57 was 188/203 and RD49 was 185/189; filled grain plant -1 in RD57 was 166.8/161; empty grain plant -1 in Chiang Phatthalung was 76.6/45.87; filled grain (%) in Chiang Phatthalung was 57.3/62.1. A highly significant correlation was found between grain yield and the number of panicle plants-1 (R=0.75; P<0.001) under non-flooded conditions, which indicated that grain yields under aerobic soil largely depended on panicle initiation. Therefore, the panicle initiation stage should first be concentrated under water shortage. Thailand comprises a wide diversity of rice. Therefore, more varieties of both modern and local Thai rice should be studied further.

Pages 233-239 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3803
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Effect of water priming on the seed moisture content and the rooting of soybean [Glycine max (L.) Merr.] ‘Fukuyutaka’ seeds under non-irrigated conditions

Naoki Honda and Genki Ishigaki*

Sumiyoshi Livestock Science Station, Field Science Education Research Center, Faculty of Agriculture, University of Miyazaki, Shimanouchi 10100-1, Miyazaki, 880-0121, Japan

Abstract
This study aimed to clarify the effect of water priming on the seed moisture and the rooting rate of soybean [Glycine max (L.) Merr.] ‘Fukuyutaka’ for developing a cultivation method, where soybean seeds can directly be sown on the meadow or grassland for livestock production. The weight of each soybean seed was measured before and after they were subjected to: no treatment (control); and, two kinds of priming treatments, soaking (2 and 4 h), and moisture absorption (3, 12, and 24 h). The weight of seeds was additionally measured after keeping them at a specified temperature (28–30°C) and humidity (58–60%) for 4 h, 1, 2, and 3 days. The moisture content of soybean seeds was calculated based on their weights pre- and post-treatment. The rooting rate of the seeds was investigated after each priming (control, soaking, and moisture absorption), 48 h of standing and irrigation treatment. The seed moisture content of soybean seeds increased immediately after priming (soaking or moisture absorption treatment), however, after standing, the moisture content in both treatments deceased to the same level as that of control. The rooting rate in both priming pre-treatments was similar to or lower than that in control, indicating that neither soaking nor moisture absorption of soybean seeds had a keeping moisture content of seeds for long time which promoting effect on rooting of soybean under dry condition on meadow or grassland.

Pages 240-243 | Full Text PDF| doi: 10.21475/ajcs.23.17.02.p3814