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The nature and magnitude of genetic effects on morpho-yield traits were studied in a 6 × 6 F 1 and F 2 diallel cross in upland cotton. An additive-dominance model was adequate for most of the traits except plant height and seed cotton yield, where the model was partially adequate. Genetic parameters were estimated following Hayman's and Mather's model. Additive effects controlled lint percentage and monopodia in both generations, and plant height and sympodia in F 2 . Non-additive inheritance with over-dominance controlled yield in both generations, and plant height and sympodia in F 1 . Most traits presented an unequal proportion of positive (U) and negative (V) alleles in the loci (H 2 < H 1 ) and an asymmetrical distribution of genes in the parents (H 2 /4H 1 < 0.25 and F different to zero). The value of H 2 /4H 1 was lower than maximum value (0.25) for all of traits, which arises when U = V = 0.5 over all loci. The proportion ͌ʳʲ 4DH1 ʲʲ + F ʲ/͌ʳʲ 4DH1 ʲʲ -F ʲ) confirmed by half of the traits that dominant alleles were in excess as compared to recessive alleles. Dominance effects (h 2 ) for most of the traits suggested that substantial contribution of dominance was not due to heterogeneity of loci in these parameters. Broad and narrow sense heritabilities were high for most of the traits. Correlation coefficient between the Wr + Vr and mid parental (y) indicated that dominant genes were responsible for increased sympodia, lint % and yield, and recessive genes increased monopodia and plant height. Genetic gain was encouraging for most traits. Cultivar CIM-1100 was identified by genetic advancement as a promising parental cultivar to cross combinations.Additional key words: additive-dominance model; additive and dominance effects; D, H 1 & H 2 genetic components of variance; seed cotton yield; upland cotton. ResumenEfectos genéticos en caracteres morfológicos y de rendimiento en algodón (Gossypium hirsutum L.)Se estudió la naturaleza y la magnitud de los efectos genéticos sobre los caracteres morfo-productivos en un cruce dialélico F 1 y F 2 de 6 × 6 en algodón tipo upland. Para la mayoría de los caracteres, excepto altura de planta y rendimiento de semilla, fue adecuado un modelo aditivo-dominante. Se estimaron los parámetros genéticos según Hayman y Mather. Los efectos aditivos controlaron el porcentaje de pelusa y los monopodios en ambas generaciones, y la altura de la planta y los simpodios en la F 2 . La herencia no aditiva con superdominancia controló el rendimiento en ambas generaciones y la altura de planta y los simpodios en la F 1 . La mayoría de los caracteres presentaron una proporción desigual de alelos positivos (U) y negativos (V) en los loci (H 2 < H 1 ) y una distribución asimétrica de los genes en los parentales (H 2 /4H 1 < 0,25 y F 0). El valor de H 2 /4H 1 estuvo por debajo del valor máximo (0,25) para todos los caracteres, lo que surge cuando U = V = 0,5 en todos los loci. La proporción ͌ʳʲ 4DH1 ʲʲ + F ʲ/͌ʳʲ 4DH1 ʲʲ -F ʲ) confirmó, para la mitad de los caracteres, que había un exc...

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Overall, maize genotypes showed early maturity in plain areas (CCRI and Haripur) but higher yield in hilly areas (Mansehra and Swat). © 2017 Society of Chemical Industry.

Iron is one of the most important micronutrients for crop plants due to its use in important physiological processes such as photosynthesis, mitochondrial respiration, metal homeostasis, and chlorophyll synthesis. Crop plants have adapted different strategies for uptake, transport, accumulation, and storage of iron in tissues and organs which later can be consumed by humans. Estimates indicate that about 2 billion people (33% of human population) are at risk of iron deficiency in which infants, children, and pregnant women are potentially compromised. Biofortification refers to the increase in concentration of micronutrients in edible parts of plants and understanding the pathways for iron accumulation in plants is necessary for breeding iron‐enriched crops. Iron‐biofortified crops are also one of the key factors in achieving multiple United Nations Sustainable Development goals. This review article covers different strategies of iron acquisition and transport in plants, its bioavailability, coping with the iron deficiency as a global perspective, the current status of iron biofortification, and how breeding future biofortified crops could be helpful in combating the said issue in a sustainable manner.

A two years study was carried out to see the effect of various herbicides and hand weeding on weed control in wheat. For weed density and grain yield highly significant differences were recorded between treatments and weedy check. The lowest weed density was observed in hand weeding (3.50) which was statistically at par with Puma super+2,4-D (5.38), Puma super+Buctril M (5.63), Dicuran MA 60 (6.13) and Tolkan (6.75) while the highest weed density was observed in the weedy check (42.38). The maximum grain yield of 2957 kg haG 1 was obtained in hand weeding and was statistically comparable with the yields of Puma super combined with 2,4-D (2649 kg haG 1) and Buctril M (2612 kg haG 1) and Dicuran alone (2556 kg haG 1). The lowest yield was exhibited by weedy check (1606 kg haG 1) and was statistically at par with Panther (2003 kg haG 1).

A half-diallel mating system was used to evaluate six wheat cultivars and their F 1 and F 2 populations for inheritance of earliness and morphological and yield traits. These genotypes were crossed in a half-diallel fashion during 2010-2011 to get 15 cross combinations. The 6 × 6 wheat F 1 and F 2 half-diallel populations and their parental cultivars were assessed in a randomized complete block design during 2011-2012 and 2012-2013, respectively. Genotypes revealed significant (P ≤ 0.01) differences for all the traits in both generations. According to scaling tests, an additive-dominance model was partially adequate for all the traits in the F 1 and F 2 generations. Diallel analysis revealed significant values for additive (D) and dominance (H 1 and H 2) genetic components of variance for majority traits in both generations, however, the overdominance type of gene action was predominant for inheritance. Additive gene action was observed for days to heading and plant height in the F 1 generation and tiller per plant and grain yield per plant in the F 2 generation. In the loci (H 2 < H 1), the majority of the traits showed an unequal proportion of positive and negative genes with asymmetrical distribution among parental genotypes (H 2 /4H 1 < 0.25). Significance of both additive and nonadditive genetic variations suggested integrated breeding strategies with delayed selection for improvement in wheat populations.

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