M.S. Basu’s research while affiliated with ICAR-Central Institute for Women in Agriculture and other places

This study was undertaken to ascertain the genetic differences in 32 genotypes for pod yield and its component traits, and morpho-physiological characters, namely carbon isotope discrimination (Δ13C), enrichment of oxygen isotopes (Δ18O), specific leaf area (SLA) and SPAD chlorophyll content (SCMR) that are known to influence water-use efficiency (WUE) in groundnut. Highly significant genotypic differences (P<0.01) were observed for Δ13C, Δ18O, SLA, SCMR, harvest index, shelling percent, plant height, and pod, kernel and haulm yields and total dry matter production. A strong inverse relationship of SCMR with SLA (r = -0.626, P<0.01) and Δ13C (r = -0.552, P<0.01) was observed. Very high broad sense heritability estimates (81%) were obtained from SCMR. Δ13C was positively associated with harvest index (r = 0.535, P<0.01) and its association with haulm yield (r = -0.617, P<0.01) and total dry matter (r = -0.522, P<0.01) were negative. The cluster analysis revealed that genotypes ICR 11 and JUG 28 were the most closely related, and GG 20 and JUG 13 were the least related genotypes. This has significance for future breeding due to the potential to produce trangressive segregrants through hybridization of these distant genotypes. The genotypes that involved ICGS 76 as one of the parents in their pedigree scored very high SCMR values.

Pot and field studies were undertaken in the main groundnut growing areas of India, to find out the diagnosis of symptoms, extent of yield losses and remedies of boron deficiency in groundnut. In sand culture pot experiments, the B deficiency showed retarded growth of the apical portion,, death of the stem apex, malformation of the leaf vein, chlorosis, necrosis of basal margins in emerging leaves. But, these symptoms were not observed in field grown groundnut crop, even on B deficient soils, where low pod filling, shriveled seeds and hollow darkening or off-colour in the center of the seed were commonly observed symptoms of B deficienc. The B deficiency caused 15-26 % yield losses in calcareous soils with 0.2 - 0.36 ppm hot water soluble B of the main groundnut growing areas. Borax and boric acid are the two commonly used boron fertilizers, in India, and their application at 0.5 -1.0 kg ha-1 B either in soil as basal or prior to bloom stage (20-30 days after emergence), or foliar application of 0.05-0.1% aqueous solution of boric acid corrected B deficiency and increased pod filling, seed size, 100-seed weight, percent sound mature seeds and finally pod yield. In field , though response of B was observed from 0.5 - 2 kg B ha-1, 1.0 kg B ha-1 was ideal for most of the groundnut cultivars. However, large seed size groundnut cultivars like TKG 19A require higher quantity of B than the normal seed-size groundnut as application of borax at 2 kg B ha-1 increased 23.3% in pod yield over control in large seed size groundnut, as against 11.7 % increase in pod yield over control in normal seed-size groundnut genotypes. But, the higher doses of B, more than 5 kg B ha-1, showed its toxicity in groundnut leaves, which reminds of its careful application. The effectiveness of various methods of application of borax or boric acid, at 1 kg B ha-1, were compared in field by applying these as seed dressing, in the soil, as foliar spray and also along with drip irrigation where the maximum response was observed when B was applied along with drip irrigation, followed by soil application. Boric acid caused scorching of leaves when applied on foliage, and as seed dressing it caused damage to seed reducing field germination. Hence, these practices should be avoided in groundnut. Thus, soil application of 1.0 kg B ha-1, either as basal or at 20-30 days after emergence, is recommended for production of well-filled and quality seeds of groundnut in India.

Bambara groundnut, an indigenous African crop cultivated for centuries from Senegal to Kenya, and Sahara to South Africa and Madagascar, is quiet similar to groundnut and remains as an underutilized legume, despite its drought tolerant cultivated in Africa only as a subsistence crop. An effort was made to introduce this crop in the Asian countries where the agro-climatic situation is similar to African countries. The bambara groundnut grows well under in Gujarat (western India) in semi-arid climate and kharif season with early July sowing is most suitable and three high yielding genotypes DODR-TZ, SB 4-2 and S19-3 with 117-133 days maturity period. The short duration genotypes AS-17, and S19-3 could be tested in the Rajasthan, Maharashtra and Gujarat where the length of growing period is short. The Bambara groundnut genotypes, growing well under field condition in Gujarat (Western India) and Andhra Pradesh (Southern India) both under semi-arid climate, should go for multilocational testing and the promising one may be released in India. There is an urgent need to increase the bambara groundnut yield through developing high yielding varieties, proper package of practices, application of nutrients and improvement of the nitrogen-fixing capacity. The bambara groundnut has great potential for incorporation into various human foods where it could provide useful plant proteins. Further studies on crop phenology is required to maximize the yield as to specify the most appropriate rate and time of specific developmental process. Though some of the bambara genotypes can grow without fertilizer, high yielding genotypes must be fertilized with 20 kg N, 50 kg P, 50 kg K and 100 kg Ca for achieving high yield and making the crop renumerative.

The groundnut(Arachis hypogeaeL.), in India, is mainly grown on light textured and calcareous soils deficient in available P where response of P is not consistent causing prominent P deficiency. Identification and use of phosphorus efficient groundnut genotypes is the best alternative for which insitu field screening was conducted in calcareous soil with 5-6 ppm available phosphorus. Seventy groundnut genotypes were grown in the field under low (unfertilized control) and high (fertilized with 50 kg P ha-1) P conditions, the growth, yield and nutrient concentrations and uptake by groundnut were studied and the genotype having superior yield responses and high P uptake, both at low and high levels of P availabilities, were selected as P-efficient. High P concentration in leaves during early growth stages and high P uptake at harvest was observed in the P-efficient genotypes. On an average, the P-efficient genotypes showed 275 g m-2 pod yield, however, the P-inefficient genotypes showed 102 g pod m-2. Based on four years of study, the genotypes GG 5, FeESG 8, FeESG 10, NRCG 1308, NRCG 3498, and SP 250A were identified as P-efficient and genotypes VRI 3, B 95, NRCG 162, PBS 16003, 20012 as P-inefficient. These P-efficient groundnut genotypes which performed well with relatively high yields both under low and sufficient P conditions are being recommended for their cultivation in low P soils, to avoid any yield losses due to P-deficiency.