January 2010

Study of genetic diversity among inter-intraspesific hybrids and original grapevine varieties using AFLP molecular markers

A. Theocharis, P. Hand, J. Pole, V. Cevik, I. Fisarakis, J. HendersonAbstract

Several grapevine varieties are grown in vineyards worldwide including interspecific (Vitis vinifera × Vitis spp), intraspecific (V. viniferaL. × V. vinifera L.) and inter×intraspecific (interspecific×intraspecific) hybrids with unknown origin, ambiguous naming and genetic identity. In this study, the genetic relations among eighteen grapevine hybrids and original varieties (Vitis vinifera L.) which have mostly been described by ampelography data were analysed using AFLP (Amplified Fragments Length Polymorphism) molecular marker technology. AFLP polymorphic fragments generated by a combination of restriction digestion and PCR amplifications were assessed for analysis of the polymorphisms among accessions. Polymorphic bands were scored and genetic similarity (GS) was calculated by Dice coefficient. Cluster analysis and principle coordinate analyses (PCO) of the results addressed the genetic distance among inter-intraspecific hybrids and original grapevine varieties; detected the level of genetic similarity between varieties and specific mutant or clone; assessed the genetic relations among varieties involved in the same pedigree; recognized same genotypes under different names (synonymes) and proposed the genetic identity for an unknown, in ampelography data variety cultivated in UK vineyards.
Pages 1-8 PDF

Effect of Different Defoliation Treatments on Yield and Yield Components in maize
(Zea mays L.) Cultivar of S.C704

Barimavandi A. R., Sedaghathoor S. and Ansari RAbstract

Plant leaves are major source of photosynthesis and obtain assimilates for growing parts. Effects of different levels of defoliation studied on maize's growth and yield. The study was conducted as completely randomized block design with 8 treatments in 4 replications. The treatments were: T₁₌ control (without leaf removal), T₂= removing of ear leaf, T₃= defoliating leaves on top of the ear, T₄= defoliating leaves under the ear, T₅= defoliating just two leaves under ear, T₆= defoliating two leaves on top of ear, T₇= defoliation whole leaves (complete defoliation) and T₈= defoliating just tassel leaf. Effects of these treatments were evaluated on the major traits of yield components. Results showed that leaves defoliation had significantly effect on grain yield, rows number on cob, grains number on cob, grain dry weight and cob length (P<1%). Leaf defoliation intensity and leaf position affected total dry matter. Complete defoliation reduced severely grains on cob. While defoliation on top of ear and underneath leaves of ear caused to reduce grains on row. The maximum LAI belonged to control and the least amount was connected to T₄. The results suggest that the top leaves should not defoliate, because this treatment has negative effect on the yield.
Pages 9-15 PDF

Evaluation of Palm oil mill effluent to maize (Zea mays. L) crop: yields, tissue nutrient content and residual soil chemical properties

Chris.O. Nwoko and Sola Ogunyemi
Abstract

Palm oil mill effluent (POME) is produced in large quantities in Nigeria and is amenable to microbial degradation. Thus, represents a low-cost source of plant nutrients. This paper presents the data from two years experiments concerned with the application of aerobically-fermented POME to soils for maize (Zea mays. L) Production at Owerri. Nigeria. Maize grain yield, height, dry matter, tissue nutrient and soil residual chemical properties were evaluated. The experimental design consisted of completely randomized block in factorial arrangement. The paper describes the results of crop yields, stover and grain N, P and K content and residual organic C, N, P and pH as influenced by soil-amendment. The research demons- trated the organic-fertilizer produced higher grain yield, dry matter, and tissue nutrient content and leaves consider- able residual organic C, N and P than plots that received no amendment (control). Fermented POME could enhance maize crop production and can promote sustainable agriculture.

Pages 16-22 PDF

Investigation on molecular phylogeny of some date palm (Phoenix dactylifra L.) cultivars by protein, RAPD and ISSR markers in Saudi Arabia

Munshi Abdulla and Osman Gamal
Abstract

Date palm (Phoenix dactylifra L.) is one of the most important fruit crops in the Middle East. Kingdom of Saudi Arabia lies among the largest date palm fruit producer worldwide. However, little knowledge is currently available about the molecular characterization of date palm cultivars in this country. Determination of genetic variability and cultivar identification in date palm are two major importance in breeding programs, characterization of germplasm, and conservation purposes. Three types of markers such as protein, RAPD-PCR, and ISSR were applied on four important cultivars in Saudi Arabia (Med300l b1, Sugay1 b1, Khalas b1 and Sukkarib1). Intervarietal variations were investigated using five RAPD and five ISSR markers. Most of the studied markers showed intervarietal polymorphism. Protein markers were also applied to assess the genetic polymorphism. Cluster analysis by UPGMA showed two main clusters. Cultivar Sukkarib1 was located on the cluster A, with Nei and Li's coefficient equal to 0.55. Cluster B consisted of 3 other cultivars, Med300lb1, Sugayb1and Khalasb1 with 0.66-0.85 Nei and Li's similarity range. Sugay b1 and Khalas b1 were the two most closely related cultivars among the four cultivars with the highest value in the similarity for Nei and Li's coefficient 0.85. Med 300l b1 was also closely related to Sugay b1 and Khalas b1 with second highest value in the similarity matrix 0.66. The average similarity among the four cultivars was a bit more than 55%. Most of cultivars had the narrow genetic diversity as already expected. The result of the analysis can be used for the selection of possible parents to generate mapping populations.

Pages 23-28

Supplemental irrigation and cultivar effects on potato tuber diseases

Olanya, O.M., G.A. Porter and D.H. Lambert

Abstract

Supplemental irrigation can improve potato growth and tuber yield under deficit rainfall conditions, but may also impact potato tuber diseases. The comparative effects of irrigation on tuber disease incidence were quantified on four cultivars. Surface sprinkler irrigation was applied in July and August of each year, based on tensiometer or moisture block readings, with the goal of maintaining soil water to the required treatment levels. Black scurf (Rhizoctonia solani), black dot (Colletotricchum coccodes), silver scurf (Helminthosporium solani) and comm- on scab (Streptomyces scabei) diseases were quantified on potato tubers randomly sampled at harvest and stored at 7.2 C. The incidence of tuber diseases varied among irrigations and significant treatment effects (P<0.05) were observed for black dot, black scurf and silver scurf diseases across years. The highest levels of black dot and black scurf disease incidences were recorded on the irrigation treatments of artificial drought and Tiaug60 in 1996 and Eaug50 and Non-irrigated check in 1997, respectively. Disease incidence differed significantly (P<0.05) among cultivars and years, and was generally greater on Superior and Shepody than on Atlantic and Russet Burbank. This study showed that supplemental irrigation may selectively impact tuber disease incidence, depending on treatment and application scheduling, while varying cultivar susceptibility may increase tuber disease levels.

Pages 29-36 PDF

Molecular and Expression Analysis of Cowpea Trypsin Inhibitor (CpTI) Gene in Transgenic Elaeis guineensis Jacq Leaves

Ismanizan Ismail, Fong Siew Lee, Ruslan Abdullah, Chan Kok Fei, Zamri Zainal, Nik Marzuki Sidik and Che Radziah Che Mohd Zain

Abstract

Cowpea trypsin inhibitor (CpTI) has been reported to have insecticidal properties against a wide range of insects. An 8-year-old insect resistant oil palm, Elaeis guineensis Jacq. variety Tenera assigned as CpTI P8 was the first transgenic oil palm tree generated by the co-transformation of pDM 402 and pCAMBIA 1301 plasmids into the immature embryos of the oil palm via particle bombardment. PCR analyses had confirmed that 100% of the tested CpTI P8 frond leaves and root tissue genomic samples showed the presence of the CpTI transgene. The partial pDM 402 expression cassette consisting of the actin promoter sequence (Act1-5’), the whole CpTI coding sequence and the Nos-3’ terminator sequence was fully recovered from the CpTI P8 genome using the Act1F1/NosTR1 primer pair in subsequent PCR analysis. Moreover, Southern blotting analysis showed the presence of two hybridized fragments, 0.96 kb and 1.2 kb in size in the BamHI-digested genomic DNA and also demonstrated the stable integration of the transgene into the CpTI P8 genome. The amplification of a 425 bp RT-PCR product using the CpTI gene-specific primer pair has clearly implicated the expression of CpTI transcript. Quantitative study on the expression of CpTI gene was carried out using SYBR Green Quantitative Real Time-Polymerase Chain Rection (QRT-PCR) assay and revealed a remarkably higher expression of CpTI in the CpTI P8 tree compared to non-transformed oil palm tree. Together, these data have proven the successful gene transfer and a 7-fold increase in CpTI transcript accumulation in the leaves of CpTI P8 tree which could ultimately confer greater resistance against insect pest invasion. Interestingly, the data in present study also suggest that a simple integration pattern contributes significantly to the stability and high transgene expression in transgenic plants.

Pages 37-48 PDF

The comparison of carbohydrate and mineral changes in three cultivars of kiwifruit of Northern Iran during fruit development

Mansour Afshar-Mohammadian, Jila Rahimi-Koldeh

Abstract

According to the result of this study, there was a significant increase in the amount of sugars including rhamnose, glucose and mannose from October for Abbot and Hayward and from August for Allison until harvesting time (late November). During one month of post harvesting time, the fruits showed no significant changes in sugar concentration except for the Hayward that showed a significant increase of glucose and mannose concentration. The concentration of fructose and inulin in Allison and Hayward did not show any significant changes during the investigated months except a decline on August and then remained constant at the first level. The concentration of these sugars in Abbott showed a similar pattern i.e. a reduction in August followed by a significant increase until harvesting time, and then remained at constant level. Soluble solid content (SSC) as an indicator of fruit maturity, in Allison was significantly more than other cultivars in harvesting time, however, this difference was not significant in late December among cultivars. The mineral analysis of the fruits indicated that the concentration of iron and phosphorus of the kiwifruit cultivars were not significantly different but, potassium concentration in Hayward and calcium concentration in Allison were significantly more than other cultivars.

Pages 49-54 PDF

Levels of a dominant Glutathione S-transferase in onion bulbs have a seasonal relationship with physiological inhibitors

M. M. Rohman, Mohammad Anwar Hossain and Masayuki Fujita

Abstract

Isoforms of onion bulb GSTs (designated as GSTa, GSTb, as minor, and GSTc, GSTd and GSTe as dominant GSTs) were separated by DEAE-cellulose chromatography, and variation in the activity of dominant GSTs was studied in winter and spring. Among the dominant GSTs, GSTc and GSTd were found to have similar activity levels in both seasons. In case of GSTe, distinct activity levels were observed in winter and spring, where, a decreased activity was found in spring. An expressional relation was observed between GSTe and physiological inhibitor, quercetin-4´-glucoside in onion calli. However, GSTe was not responsive to quercetin-3,4´-diglucoside. The concen- trations of the two inhibitors were also compared in onion bulb tissues collected from winter and spring seasons. Quercetin-4´-glucoside and quercetin-3,4´-diglucoside containing fractions, ethylacetate (EtOAc) and water fraction, were isolated from onion bulb extract, and IC₅₀s of the fractions were measured on GSTc, a sensitive GST to the inhibitors. The IC₅₀s of EtOAc- and water fraction on GSTc (in winter 84 and 283 mg ml^-1 fresh tissue, respectively, and in spring 102 and 214 mg ml^-1 fresh tissues, respectively) and HPLC profile suggested that the concentration of quercetin-4´-glucoside decreased over time of storage in onion bulb, while the concentration of quercetin- 3,4´-diglucoside increased in spring. Therefore, lower activity of GSTe in onion bulb in spring is due to lower content of quercetin-4´-glucoside in onion bulb tissues, and hence, quercetin-4´-glucoside might have important role in expressing the activity of this GST in onion bulb.

Pages 55-62 PDF

Differential accumulation of gliadin proteins in wheat grain of RILs grown at two different agroclimatic conditions and their effect on loaf volume

Elangovan M., Dholakia B.B., Gaikwad S.M., Gupta V.S.
Abstract

The end use of wheat depends on the quality and quantity of protein accumulated in the grain during the grain filling stage. Gliadin families of proteins are proved to affect the bread making quality (BMQ) by affecting the rheology and functionality of dough. The gliadin accumulation was analysed using Indian genotypes grown in two diverse agro climatic zones. About 16 RILs along with their parents HI977 and HD2329 revealed significant difference in accumulation of all gliadin fractions. High accumulation of a and ß gliadin with low level of ? gliadin was observed for Kota as compared to Pune location. However, this significant difference in gliadin accumulation due to environment, did not affect the loaf volume performance of the RILs at statistically significant level.

Pages 63-67 PDF