The development and use of microsatellite markers for genetic analysis and plant breeding with emphasis on bread wheat

In recent years, a variety of molecular markers, based on microsatellites or simple sequence repeats (SSRs) have become the markers of choice, thus necessitating their development and use in a variety of plant systems. In this review, the basic principles underlying different hybridization-based (oligonucleotide fingerprinting) and PCR based approaches (STMS, MP-PCR, AMP-PCR/ ISSR/ ASSR, RAMPs/ dRAMPs, SAMPL), making use of microsatellites, have been outlined. Different methods for enrichment of genomic libraries for microsatellites have also been outlined. Relevant literature on the subject, giving a summary of results obtained using each approach, has been reviewed and critically discussed. The review also includes a discussion on literature, which deals with the use of microsatellites in genome mapping, gene tagging, DNA fingerprinting, characterization of germplasm and cytogenetics research. Special emphasis has been laid on the genome of bread wheat, where the work done in the authors' own laboratory has also been briefly reviewed. This revised version was published online in July 2006 with corrections to the Cover Date.     

沙棘油对犬科动物(狗)消炎能力的评估

用沙棘种子油对狗(12只，性别随机)的急性消炎能力进行了研究。急性炎症试验部位都选择在狗的背部。使用游标卡尺连续7d测量皮肤上发炎部位的情况来检测沙棘种子油的消炎能力。结果说明沙棘种子油有抗炎的能力。同时使用棉球肉芽肿瘤测定法测定了沙棘种子油对狗(12只)皮肤的慢急性炎症的消炎能力。沙棘油对狗皮肤慢性炎症的抗感染能力太弱以致于无法检测到。     

Dynamics of iron under long-term application of chemical fertilizers and amendments on maize-wheat cropping sequence

Iron (Fe) is one of the essential micronutrient plays a crucial role in redox systems in cells and in various enzyme. The Fe-deficient plants have lower redox reaction and enzymatic activity. Intensive chemical fertilizer resulted in depletions of micronutrients especially Fe from the soil. To understand the dynamics of Fe under long-term fertilizer experiment the present study was initiated during 1972 at experimental farm of College of Agriculture CSK HPKV, Palampur in randomized block design with eleven treatments replicated thrice. The soil of the experimental area was silty loam, acidic in reaction and taxonomically classified as “Typic Hapludalfs.” Surface (0–20 cm) and subsurface (20–40 cm) soil samples collected after the harvest of maize (Kharif, 2008). The continuous use of chemical fertilizers and amendments for the last 36 years in maize-wheat system in an acid Alfisol brought out marked depletion in the pools of Fe as compared to buffer plots. All the pools of Fe were noticeably higher in farmyard manure (FYM) amended plots compared to zero-fertilized plots. Although, residual fraction was found to be the most dominant fraction but organically bound and exchangeable forms were found to play major role in the nutrient supply and crop productivity and nutrients’ uptake. Highest productivity of maize (2008) and wheat (2008–2009) was recorded under 100% nitrogen, phosphorus and potassium (NPK) + FYM treatment. FYM and lime treatments resulted in significantly higher uptake of all the nutrients by both the crops compared to other treatments. Organically bound fraction was found to have highest significant and positive correlation with yield and nutrient uptake of maize and wheat crops. Further, regression analysis studies too revealed that organic form was the most important pool contributing towards the variation in the above parameters. While, exchangeable and organically bound forms contributed significantly towards diethylene triamine pentaacetic acid (DTPA)-extractable Fe.     

Emulsifying and foaming properties of ultraviolet-irradiated egg white protein and sodium caseinate

The physicochemical and functional properties of ultraviolet (UV)-treated egg white protein (EW) and sodium caseinate (SC) were investigated. UV irradiation of the proteins was carried out for 30, 60, 90, and 120 min. However, the SC samples were subjected to extended UV irradiation for 4 and 6 h as no difference was found on the initial UV exposure time. Formol titration, SDS-PAGE, and FTIR analyses indicated that UV irradiation could induce cross-linking on proteins and led to improved emulsifying and foaming properties (P < 0.05). These results indicated that the UV-irradiated EW and SC could be used as novel emulsifier and foaming agents in broad food systems for stabilizing and foaming purposes.     

Performance of larval parasitoid,Bracon brevicornis on two Spodoptera hosts: implication in bio-control of Spodoptera frugiperda

Successful pest management using parasitoids requires careful evaluation of host-parasitoid interactions. Here, we report the performance of larval ecto-parasitoid wasp, Bracon brevicornis (Wesmael) on important agricultural pests, Spodoptera litura (Fabricius) and S. frugiperda (J.E. Smith). Biology of B. brevicornis was studied on different host instars under laboratory and cage setup. In no-choice assay, the parasitoid development was highest on fifth-instar S. litura larvae as the wasp laid?~?253 eggs with 62% hatching, 76% pupae formation and 78% adult emergence. Similarly, these parameters were highest on fifth instar S. frugiperda larvae (293 eggs, 57% hatching, 80% pupae formation, 70% adult emergence). In two-choice assay, B. brevicornis preferred fourth or fifth over third instar larvae of both hosts. Successful parasitism depends on host paralysis and suppression of host immunity. B. brevicornis interaction downregulated cellular immunity of both hosts as shown by reduced hemocyte viability and spreading. The percent parasitism rate of B. brevicornis was unaltered in the presence of host plant, Zea mays in cage study. 76 and 84% parasitism was observed on fifth-instar larvae of S. litura and S. frugiperda, respectively. We evaluated the performance of B. brevicornis as a biocontrol agent on S. frugiperda in maize field. Our results show 54% average reduction in infestation after release of B. brevicornis. Taken together, we report the performance of B. brevicornis on important insect pests for the first time in laboratory and field conditions. Our findings indicate that B. brevicornis is a promising candidate for integrated pest management.

     

Molecular mapping of QTLs for resistance to Fusarium wilt (race 1) and Ascochyta blight in chickpea (Cicer arietinum L.)

Fusarium wilt (FW) and Ascochyta blight (AB) are two important diseases of chickpea which cause 100 % yield losses under favorable conditions. With an objective to validate and/or to identify novel quantitative trait loci (QTLs) for resistance to race 1 of FW caused by Fusarium oxysporum f. sp. ciceris and AB caused by Ascochyta rabiei in chickpea, two new mapping populations (F_2:3) namely ‘C 214’ (FW susceptible) × ‘WR 315’ (FW resistant) and ‘C 214’ (AB susceptible) × ‘ILC 3279’ (AB resistant) were developed. After screening 371 SSR markers on parental lines and genotyping the mapping populations with polymorphic markers, two new genetic maps comprising 57 (C 214 × WR 315) and 58 (C 214 × ILC 3279) loci were developed. Analysis of genotyping data together with phenotyping data collected on mapping population for resistance to FW in field conditions identified two novel QTLs which explained 10.4–18.8 % of phenotypic variation. Similarly, analysis of phenotyping data for resistance to seedling resistance and adult plant resistance for AB under controlled and field conditions together with genotyping data identified a total of 6 QTLs explaining up to 31.9 % of phenotypic variation. One major QTL, explaining 31.9 % phenotypic variation for AB resistance was identified in both field and controlled conditions and was also reported from different resistant lines in many earlier studies. This major QTL for AB resistance and two novel QTLs identified for FW resistance are the most promising QTLs for molecular breeding separately or pyramiding for resistance to FW and AB for chickpea improvement.     

Effect of micronutrient supplementation around calving on the plasma cortisol levels of Murrah buffaloes and Sahiwal and Karan Fries cows

Micronutrients when fed around peripartum may reduce the stress induced by cortisol. With this objective, 24 Sahiwal (SW) and 24 Karan Fries (KF) cows and 24 Murrah (Mu) buffaloes were taken and divided into four groups of six each. Vitamin E (VE), zinc (Zn) and copper were supplemented from 30 days pre- to 30 days postcalving in groups 1, 2 and 3. Animals without supplementation served as control. Blood sampling was done on days 30, 15, 7 and 3 precalving; at calving; and on days 3, 7, 15 and 30 postcalving. Plasma cortisol levels were measured by ELISA. Supplementation of VE and Zn significantly (P?<?0.05) reduced plasma cortisol levels at calving and at 30 days postcalving. KF cows exhibited best results with VE, whereas SW cows and Mu buffaloes responded best to Zn. Copper increased the peripartum cortisol levels. Reduction in cortisol levels may help in keeping the animal healthy and stronger to fight immuno-suppression generally observed around the period of peripartum.