Genetics,genomics and breeding of groundnut (Arachis hypogaea L.)

Groundnut is an important food and oil crop in the semiarid tropics, contributing to household food consumption and cash income. In Asia and Africa, yields are low attributed to various production constraints. This review paper highlights advances in genetics, genomics and breeding to improve the productivity of groundnut. Genetic studies concerning inheritance, genetic variability and heritability, combining ability and trait correlations have provided a better understanding of the crop's genetics to develop appropriate breeding strategies for target traits. Several improved lines and sources of variability have been identified or developed for various economically important traits through conventional breeding. Significant advances have also been made in groundnut genomics including genome sequencing, marker development and genetic and trait mapping. These advances have led to a better understanding of the groundnut genome, discovery of genes/variants for traits of interest and integration of marker‐assisted breeding for selected traits. The integration of genomic tools into the breeding process accompanied with increased precision of yield trialing and phenotyping will increase the efficiency and enhance the genetic gain for release of improved groundnut varieties.     

Calophyllum inophyllum: recalcitrant or intermediate seed?

We studied seed storage behaviour of a multipurpose tree Calophyllum inophyllum (Clusiaseae). Seeds were collected at Roslyn bay (23°7′60″ S, 150°43’60″ E) Central Queensland. Seed drying and desiccation tolerance tests were carried out according to International Seed Testing Association (ISTA) rules. We found C. inophyllum seeds to be recalcitrant and vulnerable to chilling injury, hence, unsuited for cold storage. C. inophyllum seeds maintained their viability for an appreciable period (> 8 months) if stored in warmer environments.     

A novel serine protease cryptolepain from Cryptolepis buchanani: purification and biochemical characterization

A novel protease is purified to homogeneity from the latex of a medicinally important plant Cryptolepis buchanani of family Apocynaceae (formerly Asclepiadaceae). The enzyme named cryptolepain has a molecular mass of 50.5 kDa. The isoelectric point and extinction coefficient (epsilon280nm1%) are 6.0 and 26.4, respectively. Cryptolepain contains 15 tryptophans, 41 tyrosines, and eight cysteine residues forming four disulfide bridges. The detectable carbohydrate moiety in the enzyme was found to be 6-7%. Cryptolepain hydrolyzes denatured natural substrates like casein, azocasein, and azoalbumin with high specific activity. The protease is exclusively inhibited by serine protease inhibitors phenylmethansulfonyl fluoride and diisopropyl fluorophosphate. Hydrolysis of azoalbumin by the cryptolepain is optimal in the pH range of 8-10 and temperatures of 65-75 degrees C. The enzyme shows high stability against pH (2.5-11.5), temperature (up to 80 degrees C), and chemical denaturants. The Km value of the enzyme was found to be 10 microM with azocasein as the substrate. The N-terminal sequence of cryptolepain is unique and shows only little homology to other known serine proteases, which makes this enzyme an ideal candidate for our ongoing biochemical and structure-function investigations of proteases. Easy availability of the latex and simple purification procedures make the enzyme a good system for exploring the biophysical chemistry of serine proteases as well as applications in the food industry.     

Long‐term effects of organic manure and manufactured fertilizer additions on soil quality and sustainable productivity of finger millet under a finger millet–groundnut cropping system in southern India

In a 20‐yr‐old long‐term experiment, the impact of continuous application of organic manures and inorganic fertilizers on soil quality and the sustainability of finger millet production was conducted on two cropping systems: finger millet and finger millet–groundnut on an Alfisol of semi‐arid southern India. The study was conducted from 1992 to 2011 at the All India Coordinated Research Project for Dryland Agriculture, UAS, Bangalore, using a randomized block design. The treatments comprised of T₁: control [no fertilizer and no farmyard manure (FYM) applied], T₂: FYM 10 t/ha, T₃: FYM 10 t/ha + 50% of recommended NPK (50:50:25 kg/ha), T₄: FYM 10 t/ha + 100% of recommended NPK and T₅: 100% recommended NPK. Comparison of long‐term yield data between treatments was used to calculate a ‘sustainability yield index’ (SYI), which was greatest for T₄ (FYM 10 t/ha + 100% of recommended NPK), in both rotational (0.68) and monocropping (0.63) situations. Soil quality indices were determined using principal component analysis linear scoring functions. The key indicators which contributed to the soil quality index (SQI) under rotation were organic C; potentially available N; extractable P, K and S; exchangeable Ca and Mg; dehydrogenase activity and microbial biomass C and N. The largest SQI (7.29) was observed in T₄ (FYM 10 t/ha + 100% NPK), and the smallest (3.70) SQI was for the control. Application of 10 t/ha FYM together with NPK (50:50:25 kg/ha) sustained a mean yield of 3884 kg/ha.     

Effect of Castor Oil on Soil Erosion by Water

Soils from six different regions of the State of Uttar Pradesh, India, were treated with 1% and 2% concentrations of castor oil and incubated for 15 days and 30 days time. The erosion coefficients of natural as well as treated soils were determined with a simple laboratory erosion apparatus. The castor oil was found to be highly effective in reducing soil erosion. It was more effective in light texture soils with reduction in erosion coefficients to the extent of 88 70. Heavy textured soils also registered good reduction in erosion coefficient, to the extent of 20 %. The castor oil was effective in both the concentrations and both the incubation periods. Similarly, it was effective at all the four slope levels viz. 1, 2, 4 and 8%. The castor oil has been found much superior than cellulose and protein as far as their capability to check soil erosion is concerned.     

Productivity,profitability and sustainability of rain-fed chickpea under inorganic and biofertilization in foothills of north-west Himalayas

A 4-year (2008–2009 to 2011–2012) study was conducted on the effect of mineral phosphorus (P) + sulphur (S) and biofertilizers on rain-fed chickpea (Cicer arietinum L.) at the Punjab Agricultural University’s Research Station, Ballowal Saunkhri, India. The experiment comprised of five combinations of P and S, viz. control (P₀S₀), no P + 10 kg S ha^?1 (P₀S₁₀), 15 kg P + 10 kg S ha^?1 (P₁₅S₁₀), no P + 20 kg S ha^?1 (P₀S₂₀) and 30 kg P + 20 kg S ha^?1 (P₃₀S₂₀); and three seed inoculation levels, viz. control, Rhizobium and phosphate-solubilizing bacteria (PSB), were laid out in randomized complete block design. Combined application of P + S resulted in improved growth, nodulation, yield attributes and yield. The increase in seed yield over control due to P + S ranged from 11.8% to 17.7%. Seed inoculation with Rhizobium recorded the highest growth, nodulation, yield attributes and yield of chickpea and was statistically at par with PSB and significantly better than no inoculation. Highest benefit/cost ratio (B:C, 2.19) was obtained in P₃₀S₂₀. In view of environmental pollution and high costs of chemical fertilizers, biofertilizers alone or in combination may help to achieve sustainable and ecological agricultural production.     

Growth and Development of Soybean (Glycine max [L.] Merr.) Cultivars under Shade in Coconut Garden

The growth and development of seven soybean cultivars were studied under shade in a coconut garden. Higher shoot height, internodal elongation and lower leaf area index were the most significant growth changes noticed under shade. Leaf net photosynthesis, crop growth rate and seed yield were also reduced under shade. The cultivars CO 1, UGM 30 and UGM 37 recorded higher yield under shade when compared to other cultivars tested.