Easily measureable morpho-physiological traits as selection criteria for terminal drought tolerance in groundnut (Arachis hypogaea L.)

This study was conducted at El Obied Research Station Farm, North Kordofan State Sudan, with the objective of identifiying easily measurable morpho-physiolgical traits that could be used in drought tolerance breeding programs. Nine groundnut mutants together with three parents were evaluated under normal and terminal drought stress environments in 2003 and 2004 cropping seasons in a randomized complete block design with four replications. The genotypes did not differ significantly in the number of days to 75% emergence, with  a range of 6-8 days. Most of the measured traits showed higher values under normal than under stressed environments. Under stressed environment, some mutants like Barberton-B-30-3 and Barberton-B-30-4, exceeded their parents in pod yield (PY) /plant, dry matter production (DM) and leaf relative water content (LRWC), whereas they showed lower specific leaf area (SLA), canopy temperature (CT) and leaf senescence (LSENS) than their parents. CT, LRWC, LSENS and PY showed relatively medium broad-sense heritab-ility estimates under stress environment. PY was positively, significantly and genotypically correlated with DM and LRWC while significantly and negatively correlated with SLA, CT and LSENS under stress enviro-nment. Since these traits are reasonably heritable, strongly correlated with PY under stress enviroment and easily measurable under field conditions, they could be suggested as selection criteria for droguht tolerance in groundnut. The mutant Barberton-B-30-3, which produced the highest PY, DM and LRWC, under terminal drought stress, could be suggested as the best drought tolerant mutant in this study bending further testing over years and locations. &nbsp

The response of sorghum, groundnut, sesame, and cowpea to seed priming and fertilizer micro-dosing in South Kordofan state, Sudan

This study was undertaken with the objective of evaluating micro-dosing of mineral fertilizer combined with seed priming in sorghum, groundnut, sesame, and cowpea. On-station and on-farm trials were conducted for two consecutive seasons (2009/2010 and 2010/2011) at Al-Tukma village (12°00′57.60′′ N and 29°46′12.15′′ E) in South Kordofan State, 15 km southeast of Dilling city. Heavy cracking clay soil is the dominant soil type in the region with low fertility. The experiments for each crop consisted of two priming levels (primed seeds vs. non-primed) and four micro-doses of NPK mineral fertilizer (0, 0.3, 0.6 and 0.9 g per planting pocket or hole). On-farm trials in 15 fields consisted of control, seed priming, and seed priming + micro fertilizer (0.3 g/planting hole). Data collected included plant vigor, stand count, plant height, grain and straw yield, seed weight, and other relevant agronomic traits. This study shows that it is possible to increase productivity of sorghum, sesame, groundnut, and cowpea in the semi-arid cracking clay of South Kordofan State at a low cost and with a moderate risk for farmers through seed priming and micro-dosing of fertilizers. Seed priming combined with micro-dosing NPK mineral fertilizer of 0.9 g was the best treatment for plant establishment, seedling vigor, grain yield, and hay yield in sorghum and groundnut, whereas the combination of seed priming and 0.3 g micro-doing of fertilizer was the best in sesame. Seed priming and micro-dosing of fertilizer of 0.6 g was the best combination for cowpea. On-farm trial results indicated that priming alone and priming combined with fertilizer application significantly increased the yields of sorghum, groundnut, and cowpea over the control (P = 0.01). Of the crops tested, groundnut responded most favorably to micro-dosing and seed priming, with a value to cost ratio (VCR) of 26.6, while the highest VCR for sorghum, sesame, and cowpea was 12.5, 8.0 and 4.4, respectively. For the best productivity and profitability, we recommend using seed priming in combination with the micro-dosing of 0.9 g/hole of 15:15:15 NPK fertilizer for sorghum and groundnut, of 0.3 g/hole for sesame, and of 0.6 g/hole for cowpea grown in the semiarid South Kordofan State of Sudan