Leiser WL, Rattunde HFW, Piepho H-P, Weltzien E, Diallo A, Toure A and Hausmann BIG (2015). Phosphorous efficiency and tolerance traits for selection of sorghum for performance in phosphorous-limited environments. Crop Science 55 Published online: 27 March 2015 (DOI: 10.2135/cropsci2014.05.0392). (G7010.03.03)

Abstract: Sorghum (Sorghum bicolor (L.) Moench) is widely cultivated in West Africa (WA) on soils with low phosphorus (P) availability. Large genetic variation for grain yield (GY) under low-P conditions was observed among WA sorghum genotypes, but information is lacking on the usefulness of P-tolerance ratios (relative performance in –P [no P fertilizer] vs. +P [with P fertilizer] conditions) and measures of P-acquisition and internal P-use efficiency as selection criteria for enhancing GY under low-P conditions. We evaluated 70 WA sorghum genotypes for GY performance under −P and +P conditions for 5 yr in two locations in Mali and assessed P acquisition (e.g., P content in biomass) and P-use efficiency (e.g., grain produced per unit P uptake) traits under −P and +P conditions in one site in 2010. Significant genetic variation existed for all P-tolerance ratios across multiple sites. Photoperiod-sensitive landrace genotypes showed significantly better P tolerance and less delay of heading under P-limited conditions compared with photoperiod-insensitive varieties. Genotypic correlations of P-tolerance ratios to GY under −P were moderate. Phosphorous acquisition and P-use efficiency traits independent of harvest index were of similar importance for GY under −P conditions in statistically independent trials. However grain-P and stover-P concentrations from one −P trial showed only weak correlations with GYs in statistically independent trials. Highest predicted gains for −P GY were obtained by theoretical index selection based on −P GY combined with P-use efficiency traits (e.g., low-grain P concentration). Such index selection is expected to achieve both increased sorghum productivity and P sustainability in the P-limited WA production systems.

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Dufey I, Draye X, Lutts S, Lorieux M, Martinez C and Bertin P (2015). Novel QTLs in an interspecific backcross Oryza sativa x Oryza glaberrima for resistance to iron toxicity in rice. Euphytica Published online: 1 February 2015 (DOI 10.1007/s10681-014-1342-7). Not open access; view abstract. (G3005.10)

Leiser WL, Olatoye MO, Rattunde HFW, Neumann G, Weltzien E and Haussmann BIG (2015). No need to breed for enhanced colonization by arbuscular mycorrhizal fungi to improve low-P adaptation of West African sorghums. Plant and Soil Published online: 14 March 2015 (DOI: 10.1007/s11104-015-2437-1). Not open access; view abstract. (G7010.03.03)

Azam F, Chang X and Jing R (2015). Mapping QTL for chlorophyll fluorescence kinetics parameters at seedling stage as indicators of heat tolerance in wheat. Euphytica 202(2):245–258 (DOI: 10.1007/s10681-014-1283-1). First published online in October 2014. (G7010.02.01)

Abstract: High temperature or heat stress is one of the most important abiotic stresses that affect wheat production in almost every part of the world. Parameters of chlorophyll fluorescence kinetics (PCFKs) are the most powerful and reliable characters available to understand the impact of various abiotic stresses on plant physiological processes and heat tolerance. The present research was aimed to identify genomic regions controlling PCFKs at early growth stages of wheat through quantitative trait loci analysis by applying heat stress for different duration of time. A doubled haploid population derived from the cross of two Chinese wheat cultivars Hanxuan 10 and Lumai 14 was exposed to 38 °C for 2, 4, 6 and 8 h of heat stress and PCFKs (initial fluorescence, maximum fluorescence, variable fluorescence and maximum quantum efficiency of photosystem II) were measured. A total of 37 QTLs were identified for the target traits, among which 13 were detected under normal temperature of 25 °C and the remaining 24 under the stressful temperature of 38 °C. Stable or consistently expressed QTLs for initial, maximum and variable fluorescence were detected on chromosomes 1A, 1B, 2B, 4A and 7D. In addition, 24 QTLs were clustered in 9 clusters on chromosomes 1A, 1B, 2B, 3B, 3D, 4A, 5A and 7D. These QTL hot spot regions along with stable QTLs should be targeted for better understanding the genetic basis of chlorophyll fluorescence kinetics parameters in future mapping studies.

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Zhang L, Li H and Wang J (2015). Linkage analysis and map construction in genetic populations of clonal F1 and double cross. G3 5(3):427–439 (DOI:10.1534/g3.114.016022). (G8009.10)

Abstract: In this study, we considered four categories of molecular markers based on the number of distinguishable alleles at the marker locus and the number of distinguishable genotypes in clonal F1 progenies. For two marker loci, there are nine scenarios that allow the estimation of female, male, and/or combined recombination frequencies. In a double cross population derived from four inbred lines, five categories of markers are classified and another five scenarios are present for recombination frequency estimation. Theoretical frequencies of identifiable genotypes were given for each scenario, from which the maximum likelihood estimates of one or more of the three recombination frequencies could be estimated. If there was no analytic solution, then Newton-Raphson method was used to acquire a numerical solution. We then proposed to use an algorithm in Traveling Salesman Problem to determine the marker order. Finally, we proposed a procedure to build the two haploids of the female parent and the two haploids of the male parent in clonal F1. Once the four haploids were built, clonal F1 hybrids could be exactly regarded as a double cross population. Efficiency of the proposed methods was demonstrated in simulated clonal F1 populations and one actual maize double cross. Extensive comparisons with software JoinMap4.1, OneMap, and R/qtl show that the methodology proposed in this article can build more accurate linkage maps in less time.

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Joshi P and Yasin M (2015). Interrelationship among yield and yield contributing traits in RILs and their parents in Chickpea (Cicer arietinum L.). Indian Journal of Applied and Pure Biology 30(1):97–100. (G7009.02)

Abstract: Two hundred fifty two recombinant inbred lines generated from diverse Desi (ICC 283) and Kabuli (ICC 8261) parents were grown in RBD during rabi 2011-12 and interrelationship amongst yield traits was worked out. Seed yield showed positive association with biological yield, harvest index & plant height and negative with days to 50% flowering & days to maturity. Good plant vigour with high biological yield & plant height directly affect the yield. Long reproductive phase influence the high sink transfer and resulted high harvest index. Late flowering and late maturity observed in prostrate and spreading plant growth habit bearing RILs showed negative association with seed yield. The path analysis showed biological yield, plant height and harvest index is directly contributing to seed yield but delayed flowering and maturity increase vegetative period and reduce reproductive phase specially in prostrate and spreading plant growth habits bearing RILs showed negative indirect effect on seed yield.

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Monkham T, Jongdee B, Pantuwan G, Sanitchon J, Mitchell JH and Fukai S (2015). Genotypic variation in grain yield and flowering pattern in terminal and intermittent drought screening methods in rainfed lowland rice. Field Crops Research 175:26–36 (DOI: 10.1016/j.fcr.2015.02.003). Not open access; view abstract. (G3008.06)

Amelework B, Shimelis H, Tongoona P, Laing M and Mengistu F (2015). Genetic variation in lowland sorghum (Sorghum bicolor (L.) Moench) landraces assessed by simple sequence repeats. Plant Genetic Resources Published online: 26 June 2014 (DOI: 10.1017/S1479262114000744). Not open access; view abstract.

Abakemal D, Shimelis H, Derera J and Semagn K (2015). Genetic purity and patterns of relationships among tropical highland adapted quality protein and normal maize inbred lines using microsatellite markers. Euphytica Published online: 23 December 2014 (DOI 10.1007/s10681-014-1332-9). Not open access; view abstract.

Wang SG, Jia SS, Sun DZ, Wang HY, Dong FF, Ma HX, Jing RL and Ma G (2015). Genetic basis of traits related to stomatal conductance in wheat cultivars in response to drought stress. Photosynthetica 53(2):299–305 (DOI: 10.1007/s11099-015-0114-5). Not open access; view abstract. (G7010.02.01)