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Photoperiod insensitivity plays an important role in the adaptation of peanut (Arachis hypogaea L.) genotypes across environments. However, little is known of its genetic control. The objective of this study was to determine the combining ability of response to photoperiod in peanut. The [F.sub.1] progenies from a six-parent diallel cross excluding reciprocals were studied together with their parents for response to photoperiod under short and long day conditions in the field for three seasons. The experiment was conducted in a split plot design with photoperiod as main plots and genotype as subplots. The response to photoperiod ([D.sub.SL]) was computed as the difference in harvest index (adjusted pod weight/adjusted biomass) between short and long day treatments. The mean square for response to photoperiod was highly significant for parents and their crosses. Season by cross interaction was the only significant interaction effect. The response to photoperiod was mainly associated with general combining ability variance. ICG 2405 and ICGV 86031 were good general combiners for insensitivity to photoperiod. All crosses of sensitive x sensitive and sensitive X insensitive parents were sensitive to photoperiod. However, in several cases, this response was not consistent across seasons and resulted in a significant season X cross interaction. The [F.sub.1] between insensitive parents was insensitive to photoperiod in the three seasons tested. A comparison of [F.sub.1] response with parents and midparent value of crosses between photoperiod sensitive and insensitive parents suggested additive gene action in some crosses and partial dominance to dominance in others., Crop improvement programs in International Agricultural Research Centers distribute their improved germplasm worldwide. Very often, this germplasm is selected in relatively few test environments. How this material will perform outside [...]

Improved Spanish peanut (Arachis hypogaea L. subsp. fastigiata var. vulgaris) germplasm ICGV 91278 (Reg. no. GP-98, PI 614083), ICGV 91283 (Reg. no. GP-99, PI 614084), and ICGV 91284 (Reg. no. [...]

ICGV 94361 (Reg. no. GP-101, PI 614086) is an improved Spanish peanut (Arachis hypogaea L. subsp. fastigiatu var. vulgaris) germplasm, developed at the International Crops Research Institute for the Semi-Arid [...]

ICGV 93470 (Reg. no. GP-102, PI 614087) is an improved Spanish peanut (Arachis hypogaea L. subsp. fastigiata var. vulgaris) germplasm, developed at the International Crops Research Institute for the Semi-Arid [...]

ICGV 87354, a drought tolerant peanut (Arachis hypogaea L. Fabaceae subsp. hypogaea var. vulgaris) germplasm (Reg. no. GP-97, PI 568164) was released in 1999 by the Plant Materials Identification Committee [...]

`Jeokwangtangkong' peanut (Arachis hypogaea L. subsp. fastigiata var. vulgaris) (Reg. no. CV-63, PI 607913) is a spanish-type developed at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, [...]

Four peanut (Arachis hypogaea L.) germplasm lines, ICGV 99001 (Reg. no. GP-118, PI 631072), ICGV 99003 (Reg. no. GP-119, PI 631073), ICGV 99004 (Reg. no. GP-120, PI 631074), and ICGV [...]

ICGV 92267 (Reg. no. GP-116, PI 630947) is an improved Spanish peanut (Arachis hypogaea L. subsp, fastigiata var. vulgaris Harz) germplasm line, bred at the International Crops Research Institute for [...]

ICGV 93382 (Reg. no. GP-117, PI 630948) is an improved Spanish peanut (Arachis hypogaea L. subsp. fastigiata var. vulgaris) germplasm line bred at the International Crops Research Institute for the [...]

Pigeonpea is a major pulse crop in India. However, its productivity, which hovers around 700 kg ha-1, has remained stagnant over the past several decades. Local landraces dominate the cultivation of pigeonpea in the country. A major reason for low productivity in pigeonpea is the nonavailability of quality seed of improved varieties to farmers. In this article, we share experiences of farmer-participatory pigeonpea seed production in Fatehpur and Kanpur Dehat districts in Uttar Pradesh in India. Through farmer-participatory varietal selection trials, farmers identified NA 1, long-duration pigeonpea variety and UPAS 120, short-duration variety, as their preferred choices. Long-duration variety NA 1 was preferred because of its disease resistance, higher yield, attractive seed size and color. Farmers were organized to form cooperative societies to undertake seed production, processing and marketing at the local level. Societies were also linked with the public sector seed producing agencies to participate in the formal seed production program. The C: B ratio of seed production of NA 1 variety was 1: 5.19 as compared to 1: 2.53 of the local variety. Village-level seed production not only addressed the issue of shortage of quality seeds but also brought higher incomes to farmers leading to improved livelihood. [ABSTRACT FROM AUTHOR]

Examines the photoperiod effects on seed quality traits in peanut, a rich source of oil, protein, minerals and vitamins. Photoperiod insensitivity in adaptation of crop genotypes across diverse environments; Photoperiod effect in peanut during the post-flowering reproductive development and phenology; Influence of temperature on plant and pod growth rates in peanut.

Presents information on studies relating to the registration process of germplasm. Names of the germplasm; Benefits to be derived from the use of the germplasm; Who authorized the registration of germplasm.

Reports on the development of ICGV 92267, an improved Spanish peanut germplasm line, at the International Crops Research Institute for the Semi-Arid Tropics in Patancheru, Andhra Pradesh, India. Origin of ICGV 92267; Plant decsription.

Studies the inheritance of fresh seed dormancy in crosses involving three genotypes of Spanish peanut. Crossing of two dormant and one non-dormant genotypes; Evaluation of fresh seeds from mature pods from three genotypes; Examination of the backcross populations for their dormancy by germination test.

Presents information on the registration of the spanish peanut, ICGV 86143 germplasm which was developed in Tamil Nadu, India. Who released it; Average pod yield of the peanut; Characteristics of the peanut; Additional related information.

Abstract: Intermittent drought is the most important yield limiting factor affecting groundnut (Arachis hypogaea L.) production in rain-fed regions of Sub-Saharan Africa and Asia. Improvement of crop adaptation to drought is needed and this starts by having a thorough assessment of a large and representative set of germplasm. In this study, 247 lines belonging to the reference collection of groundnut were assessed under well-watered (WW) and intermittent water stress (WS) conditions in India and Niger for two years, following similar experimental protocols. The WS treatment reduced pod yield (31–46%), haulm yield (8–55%) and the harvest index (1–10%). Besides a strong treatment effect, yield differences within locations and years, were attributed to both genotypic and genotype-by-treatment interactions. Pod yield under WW and WS conditions were closely related in both years (Patancheru, r 2 =0.42 and r 2 =0.50; Sadore, r 2 =0.22 and r 2 =0.23). By contrast, within location and treatment, pod and haulm yields were affected predominantly by genotype-by-year (G×Y) effects, especially under WS. Within treatment across locations and years, pod and haulm yields were mostly ruled by genotypic effects, which allowed identifying a group of entries with contrasting pod yield across locations under WS. However, genotype and genotype by environment (GGE) biplot analyses distinguished India from Niger, suggesting that the selection remains environment-specific and also revealed dissimilarity between years in Niger. A close relationship was observed between yield and pod growth rate (r 2 =0.51), and partition (r 2 =0.33) under WS conditions, whereas no significant relationship was found between yield under WS and SCMR, or specific leaf area (SLA). These results showing a close interaction between the environmental conditions and the genotypic response to intermittent drought shows the necessity to carefully choose environments that truly represent target environments. This is an important result in the current breeding context of marker-assisted recurrent selection or genome-wide selection. This work opens also new ways for the breeding of drought tolerant groundnut, by bringing new highly contrasting lines currently used for crossing and deciphering drought adaptation traits to better understand G×E interactions, while it challenges the relevance of long-time used surrogates such as SCMR or SLA. [Copyright &y& Elsevier]

Abstract: Transpiration efficiency (TE) has been recognized as an important source of yield variation under drought stress in groundnut. Here the variation for TE is evaluated in a set of 318 recombinant inbred lines (RILs) of groundnut at F8 generation, derived from a cross between a high TE (ICGV 86031) and a low TE (TAG 24) parent, and the value of specific leaf area (SLA), SPAD chlorophyll meter readings (SCMR) and carbon isotope discrimination (Δ13C) as surrogates of TE are measured. Transpiration efficiency was measured gravimetrically in the 318 RILs and parents under progressive soil drying in a pot culture in two post-rainy seasons. Large and consistent variation for TE existed among the RILs across years. The overall distribution of TE among the RILs indicated that TE was governed by dominant and additive genes. Surrogates SLA and SCMR, were measured prior, during and after completion of the drought period, whereas Δ13C was measured on the dried tissue after harvest. Transpiration efficiency was negatively associated with SLA after the completion of stress treatment (r 2 =0.15) and Δ13C in leaves (r 2 =0.13) and positively associated with SCMR during stress (r 2 =0.17). These associations, all fairly weak, were significant only in 2004. None of these relationships was found in 2005. Although the heritability of SCMR during 2005 was relatively higher than that of TE, and although SCMR has previously been used to identify contrasting germplasm for TE, the stress-dependence of the relationship with TE, and the poor regression coefficients (r 2) with that RIL population, do not confer that these surrogates are adequately robust enough in that population. Though more time consuming, a direct gravimetric evaluation for TE appeared to be more reliable. [Copyright &y& Elsevier]

Tolerance to high soil and air temperature during the reproductive phase is an important component of adaptation to arid and semi-arid cropping environments in groundnut. Between 10 and 22 genotypes were screened for tolerance to high air and soil temperature in controlled environments. To assess tolerance to high soil temperature, 10 genotypes were grown from start of podding to harvest at ambient (28 °C) and high (38 °C) soil temperatures, and crop growth rate (CGR), pod growth rate (PGR) and partitioning (ratio PGR:CGR) measured. To assess tolerance to high air temperature during two key stages—microsporogenesis (3–6 days before flowering, DBF) and flowering, fruit-set was measured in two experiments. In the first experiment, 12 genotypes were exposed to short (3–6 days) episodes of high (38 °C) day air temperature at 6 DBF and at flowering. In the second experiment, 22 genotypes were exposed to 40 °C day air temperature for 1 day at 6 DBF, 3 DBF or at flowering. Cellular membrane thermostability (relative injury, RI) was also measured in these 22 genotypes. There was considerable variation among genotypes in response to high temperature, whether assessed by growth rates, fruit-set or RI. Pod weight at high soil temperature was associated with variation in CGR rather than partitioning. Flowering was more sensitive to high air temperature than microsporogenesis. Genotypes tolerant to high air temperature at microsporogenesis were not necessarily tolerant at flowering, and nor was tolerance correlated with RI. Six genotypes (796, 55–437, ICG 1236, ICGV 86021, ICGV 87281 and ICGV 92121) were identified as heat tolerant based on their performance in all tests. These experiments have shown that groundnut genotypes can be easily screened for reproductive tolerance to high air and soil temperature and that several sources of heat tolerance are available in groundnut germplasm. [Copyright &y& Elsevier]