Influence of Variable Amounts of Irrigation Water and Nitrogen Fertilizer on Growth, Yield and Water Use of Grain Sorghum

Sorghum hybrid CSH-6 was grown in fields in Delhi, India between July–November 1986 in order to study the effect of nitrogen nutrition and irrigation on dry matter accumulation, grain yield and water use. The treatments included 40 Kg Nha⁻¹ combined with two irrigations (30 DAS, 60 DAS), one irrigation (60 DAS) and no irrigation respectively. Rainfall during the crop season was only 17 cm. The unirrigated plants were considerably water stressed and exhibited very low leaf water potential, less leaf area, delayed anthesis, longer crop duration but shorter grain filling duration. The ears showed sterility and yield was only 0.41 t ha⁻¹ without nitrogen fertilization. Addition of nitrogen fertilizer had no significant effect on yield in unirrigated plants. A single irrigation 60 DAS increased yield due to increase in both grain number and grain weight per ear in fertilized and unfertilized crop respectively. Two irrigations in the unfertilized crop increased the yield to 2.2 t ha⁻¹ while similar treatment in the fertilized crop did not increase the yield significantly. Irrigation increased the WUE for grain yield. The results indicate that nitrogen stress and water stress reduced grain yield primarily through grain number rather than grain weight. Irrigation relieved both water stress and nutrient stress. Nitrogen nutrition was not beneficial under severe water stress conditions but was considerably helpful under mild stress. Biomass, grain yield and harvest index show significant correlation with preanthesis water use.     

The studies on nutrient balances in crossbred cattle bulls fed chopped green sugarcane tops supplemented with some agro industrial by- products

Fifteen adult crossbred cattle bulls, 18-22 months old (mean body weight 286.33 + 9.43) were divided into 3 groups following RBD design and were fed sugarcane tops (SCT) supplemented with some agro-industrial byproducts and concentrate feeds to determine nitrogen, Ca and P in crossbred cattle bull. For this purpose, crossbred cattle bulls were fed for 30 days ad lib SCT supplemented with Wheat bran (WB), Lentil chuni (LC) and WB + LC (50:50) in Group I, II, and III respectively. The balance values were 15.28 + 2.70, 26.85 + 4.35 and 18.00 + 3.17 for nitrogen, 11.77 + 1.34, 12.94 + 2.96 and 15.38 + 1.15 for calcium, 11.74 + 0.64, 11.26 + 1.58 and 11.69 + 0.79 for phosphorus in group I, II and III, respectively. There were no significant differences among the experimental groups in Ca and P balance values but balance of nitrogen was significantly (P < 0.05) higher in group II as compared to group I and III. It may indicated that the rumen fermentation was more appropriate in group III where animals were fed 50% lentil chuni and 50% wheat bran (supplementation of both protein and energy).     

Ontogeny and development of the gastrointestinal system in Indian walking catfish (Clarias magur) during its early development

Fish Physiology and Biochemistry - Ontogeny of the digestive tract and its accessory organs and their further development in the Indian walking catfish (Clarias magur) were examined in larvae,...     

α-Amylase inhibitor in local Himalyan collections of Colocasia: Isolation, purification, characterization and selectivity towards α-amylases from various sources

The α-amylase inhibitor from corms of Colocasia collected from Bhota village of Hamirpur district, Himachal Pradesh was purified to 17.21 folds with 61.61% recovery using ammonium sulfate precipitation, gel filtration chromatography (sephadex G-200) and ion exchange chromatography (DEAE-sephadex). A single band of the purified inhibitor was obtained by Native-PAGE. SDS-PAGE revealed the purified inhibitor to be a monomer with molecular weight of 13,900 daltons. The nature of inhibition was found to be of non-competitive type as determined by Lineweaver-Burk plot and a K_i value of 0.54 nmole was obtained by Dixon’s plot. The inhibitor was found to be heat stable and retained 81.50% activity at 70 °C temperature. Inhibitor was found to have pH optima of 6.9. The purified inhibitor was found to have inhibitory activity against α-amylases extracted from the larvae of Callosobruchus chinensis, Tribolium castaneum, Corcyra cephalonica and midgut α-amylase of Spodoptera littoralis. 100% larval mortality of C. cephalonica was observed when fed on wheat flour mixed with 0.0036% (w/w) of purified inhibitor. Purified α-amylase inhibitor was found to inhibit the activity of human salivary α-amylase. It also had inhibitory activity against potato α-amylases and reduced sugar content in treated potato slices. The purified inhibitor was found to be a glycoprotein. In the present study, the ability of the inhibitor to inhibit insect amylases highlights its possible role in pest resistance and post harvest decay of crop plants. Inhibitory activity of α-amylase inhibitor against mammalian amylases could suggest its potential in treatment of diabetes and cure of nutritional problems, which result in obesity.     

Stay green trait: variation, inheritance and its association with spot blotch resistance in spring wheat (Triticum aestivum L.)

One thousand four hundred and seven spring wheat germplasm lines belonging to Indian and CIMMYT wheat programs were evaluated for stay green (SG) trait and resistance to spot blotch caused by Bipolaris sorokiniana during three consecutive crop seasons, 1999–2000, 2000–2001 and 2001–2002. Disease severity was recorded at six different growth stages beginning from tillering to late milk stage. SG trait was measured by following two approaches: difference for 0–9 scoring of green coloration (chlorophyll) of flag leaf and spike at the late dough stage (GS 87) and a new approach of leaf area under greenness (LAUG). Germplasm lines showed a wide range (7–89) for LAUG and were grouped into four viz., SG, moderately stay green, moderately non-stay green and non-stay green (NSG). However, very few (2.2%) lines showed high expression of SG trait, i.e., LAUG >60. LAUG appeared to be a better measure of SG trait than a 0–9 scale. Mean spot blotch ratings of SG genotypes were significantly lower than those of NSG genotypes at all growth stages. Two spot blotch resistant genotypes (Chirya 3 and Chirya 7) having strong expressions of SG trait were crossed with NSG, spot blotch susceptible cv. Sonalika. Individually threshed F₂ plants were used to advance the generations. SG trait and spot blotch severity were recorded in the parents and F₁, F₃, F₄, F₅, F₆ and F_6–7 generations under disease-protected and inoculated conditions. SG trait in the F₁ generation was intermediate and showed absence of dominance. Evaluation of progenies (202–207) in the segregating generations revealed that SG trait was under the control of around four additive genes. Lines homozygous for SG trait in F₄, F₅, F₆ and F_6–7 generations showed significantly lower mean area under disease progress curve (AUDPC) for spot blotch than those with NSG expression. A positive correlation (0.73) between SG trait and AUDPC further indicated a positive influence of SG on severity of spot blotch. The study established that variation for SG trait exists in spring wheat; around four additive genes control its inheritance in the crosses studied and there is positive association between SG trait and resistance to spot blotch.     

Differential cadmium stress tolerance in wheat genotypes under mycorrhizal association

Arbuscular mycorrhizal (AM) fungi display efficient association with the land plants and is known to protect plants against various abiotic stresses including heavy metal stress. This work reports the synergistic effects of natural genotypic variation and AM association in cadmium (Cd) stress alleviation. Two genotypes of wheat viz. RAJ 4161 (resistant) and PBW 343 (sensitive) were subjected to different concentrations of Cd (0, 100, 200 and 300 mg Cd kg^?1 soil) for 30 days. Cd application resulted in increased lipid peroxidation and decreased plant growth. However, AM inoculated RAJ 4161 displayed significantly higher ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD) activity and calcium (Ca), iron (Fe)and zinc (Zn) concentration in plants. The coordination of increased antioxidant activity and high nutrient content in RAJ 4161 indicated better protective mechanism as compared to PBW 343.     

Genetic parameter estimations and genomic insights for teat and udder structure in young and mature Canadian Angus cows

Poor teat and udder structure, frequently associated with older cows, impact cow production and health as well as calf morbidity and mortality. However, producer culling, for reasons including age, production, feed availability, and beef markets, creates a bias in teat (TS) and udder scores (US) assessed and submitted to the Canadian Angus Association for genetic evaluations toward improved mammary structure. In addition, due to the infancy of the reporting program, repeated scores are rare. Prior to the adoption of genetic evaluations for TS and US in Canadian Angus cattle, it is imperative to verify that TS and US from young cows are the same traits as TS and US estimated on mature cows. Genetic parameters for TS and US from all cows (n = 4,192) and then from young cows (parities 1 and 2) and from mature cows (parity ≥ 4) were estimated using a single-trait animal model. Genetic correlations for the traits between the two cow age groups were estimated using a two-trait animal model. Estimates of heritability (posterior SD [PSD]) were 0.32 (0.07) and 0.45 (0.07) for young TS and US and 0.27 (0.07) and 0.31 (0.07) for mature TS and US, respectively. Genetic correlation (PSD) between the young and mature traits was 0.87 (0.13) for TS and 0.40 (0.17) for US. Genome-wide association studies were used to further explore the genetic and biological commonalities and differences between the two groups. Although there were no genes in common for the two USs, 12 genes overlapped for TS in the two cow age groups. Interestingly, there were also 23 genes in common between TS and US in mature cows. Based on these findings, it is recommended that producers collect TS and US on their cow herd annually.     

Identification and revealing the potential traits of the unique germplasm with extended funiculus in pea (Pisum sativum L.)

Genetic Resources and Crop Evolution - An atypical morphotype of pea (Pisum sativum L.) was identified during the germplasm characterization programme at the Indian Council of Agricultural...