International Journal of Plant Breeding and Genetics

International Journal of Plant Breeding and Genetics ISSN: 3167-5891 Vol. 3 (5), pp. 211-225, October, 2016. © International Scholars Journals

Full Length Research Paper

Ability of drought selection indices to identify the best drought tolerant and high yielding genotypes in Mediterranean environment

Saad Rahab Eddie^{1, 2}*, Ahmed L. Hadje², Adel G. Batma³ and Mohammed Taarabt ⁴

¹National Institute of Agricultural Research, BP 578, Meknès, Morocco.

²Hassan II Veterinary and Agronomy Institute, BP 6202, Rabat, Morocco.

³National Institute of Agricultural Research, BP 589, Settat, Morocco.

⁴University Mohammed VI Polytechnique, UM6P, Benguerir, Morocco.

E-mail: [email protected]

Accepted 22 August, 2016

Abstract 

Drought is the most severe production constraint for wheat worldwide. Evaluating performance of bread wheat lines and predicting drought tolerance is an essential part of the breeding process. The objective of this study is to investigate the efficiency of several indices in identifying wheat genotypes combining drought tolerance and high yield potential. Twenty-four indices, which were most frequently used in plant breeding, were compared based on grain yield of 40 bread wheat genotypes grown under two contrasting environments (stressed and non-stressed) during 2 cropping seasons 2014 and 2015. The trials were laid out as completely randomized block design of 3 replicates. Experienced stress was moderate because it caused less than 50% reduction in yield in both seasons. Analysis of variance of grain yield showed significant differences among genotypes, years, sites and genotype × site interaction. All drought indices revealed significant differences among genotypes in both seasons, except GM, SNPI and ATI. Based on correlations and principal component analysis, repeatable strong positive correlations were found between the indices (MP, MRP, REI, GMP, STI, MSTIk1, MSTIk2, HM and RDY) and grain yield under both moisture conditions during the two seasons. These indices can be considered as suitable criteria for selection of drought tolerant and high yielding genotypes under moderate stress Mediterranean environment. Moreover, these indices were able to select the highest mean yields under 20% of selection pressure with low variation across environments; especially STI, GMP and MP. The genotypes “Gladius” (9) and “AUS30355” (11) were consistently selected in both environments during two cropping seasons.

Key words: Triticum aestivum, drought stress, tolerance indices, grain yield.

International Journal of Plant Breeding and Genetics ISSN: 3167-5891 Vol. 3 (4), pp. 200-210, September, 2016. © International Scholars Journals

Full Length Research Paper

Improvement of lodging resistance of Sakha102 rice cultivar under different rates of nitrogen fertilizer

Faten O. Hassan¹*, Adel Ghali Elwi¹, Gamal Nasser Waked ¹ and Youssef F. Tork²

¹Rice Research & Training Center, Field Crops Research Institute, Agricultural Research Center, 33717, Sakha-Kafr El-Sheikh, Egypt.

²Center Laboratory for Agriculture Climate (CLAC), Agriculture Research Center, P. O. Box 296, Imbaba, 12411, Giza, Egypt.

E-mail:  [email protected]

Accepted 21 August, 2016

Abstract

Lodging of rice in Egypt reduces production and may be related to the agronomic practices. A 2-years field experiment was conducted at the Experimental Farm of Rice Research and Training Center, Kafr El-Sheikh, Egypt, during two growing summer seasons of 2013 and 2014 to study the effect of growth regulators application at different nitrogen levels on lodging resistance and productivity of Sakha102 rice cultivar. Nitrogen levels 0, 110 and 165 kg N ha^-1 in the form of urea (46.5%N) were allocated in the main plots while, growth regulators and potassium sulfate (48% K₂O) were allocated in the subplots. Growth regulators (Cycocel and benzyladenine) and K₂O were applied as foliar application at 15 and 30 days after transplanting. Cycocel, benzyladenine and K₂O were applied at the concentration of 80 ppm, 15 ppm and 2%, respectively. Data indicated that most of the studied characters increased significantly by nitrogen and growth regulators application. Application of nitrogen increased lodging area, while application of different growth regulators reduced the rice lodging area especially at the high level of nitrogen. Leaf area index at 50 days after transplanting (DAT), plant height (cm) at harvest, number of panicles m^-2, grain yield t ha^-1 and NPK uptake were correlated significantly and positively with lodging area percentage, while 1,000-grain weight (g) correlated significantly and negatively with lodging area percentage.

Key words: Lodging, growth regulators, benzyladenine, cycocel, nitrogen, potassium.

International Journal of Plant Breeding and Genetics ISSN: 3167-5891 Vol. 3 (3), pp. 189-199, August, 2016. © International Scholars Journals

Full Length Research Paper

Assessment of the response of tropical maize inbred lines in resistance to B. fusca and C. partellusin Eastern Africa.

Richard O. Odinga^1,2*, Joyce C. Karua¹, Thomas G. Awori³ and C. K. nicholas^1,2

¹African Centre for Crop Improvement (ACCI), University of KwaZulu-Natal, P/Bag X01, Scottsville, 3209, KwaZulu-Natal, South Africa.

²Kenya Agricultural and Livestock Research Organization (KALRO), P. O. Box 57811-00200, Nairobi, Kenya.

³International Maize and Wheat Improvement Center (CIMMYT), P. O. Box 1041-00621, Village Market, Nairobi, Kenya.

Email: [email protected] 

Accepted 7 July, 2016

Abstract

Stem borers, Busseola fusca (Fuller) Noctuidae, Lepidoptera and Chilo partellus (Swinhoe) Pyralidae, Lepidoptera, are serious insect pests of maize. However, genotypes showing exclusive resistance to each of these borers and with resistance to both species have not been identified in Kenya. The objective of this study was to evaluate tropical maize inbred lines for resistance to the two species. 112 maize inbred lines were artificially infested with the stem borers at three sites in Kenya. Each row of each line received three different treatments in different parts, namely infestation with B. fusca larvae, infestation with C. partellus larvae, and protection with beta 25 g/L cyfluthrin pesticide. Data was collected on leaf feeding damage rating, cumulative stem tunnel length, number of exit holes, number of dead-hearts, stalk strength and selected agronomic traits. There were significant differences among the test genotypes, (p<0.01) for resistance to B. fusca and C. partellus, for all the traits measured. The results also showed that most of the test genotypes were susceptible to B. fusca and less so to C. partellus. Twenty one (21) lines showed resistance to both B. fusca and C. partellus in at least two sites, and only four lines showed resistance to both species across the locations. Among all the test genotypes, 26 lines showed resistance to C. partellus only, while five entries had resistance to B. fusca only. Furthermore, 84 and 28 entries showed susceptibility to B. fusca and C. partellus, respectively. The others were categorized as either moderately resistant or moderately susceptible to either species. The identified inbred lines variously resistant to B. fusca and C. partellus may be used as parents in hybrid breeding programmes that emphasize stem borer resistance or as sources of resistance in breeding programs.

Key words: Busseola fusca, Chilo partellus, combined resistance, tropical maize inbred lines.

Levels of diversity and population structure present in Banana cultivars distributed in various genome groups

Motilal N. Sarabhai¹*, Rajiv B. Abdul² and Asha Mittal Kurien¹

¹Department of Botany, University of Kerala, Kariavattom, Thiruvananthapuram 695581, India.

²Department of Biotechnology, National Institute of Technology Calicut, Kozhikode, India.

E-mail: [email protected]

Accepted 15 June, 2016

Abstract 

Banana and plantain (Genus: Musa; Family: Musaceae) are giant perennial rhizomatous herbs native to South East Asia and Western Pacific. Present study analyzed the genetic population structure and diversity of South Indian Musa cultivars belonging to different genome groups using random amplified polymorphic (RAPD) markers. The total genetic diversity for all groups (Ht) was 0.22 and within groups (Hs) was 0.07 indicating high genetic variability among groups (Gst=0.69). Gene flow (Nm) was also found to be relatively very low with a value of 0.23. Genetic variability parameters and AMOVA revealed that genetic diversity is mainly present among the genome groups. Analysis of genetic diversity and structure revealed highest diversity and heterozygosity in AA group followed by AAB. Nei (1973) gene diversity was 0.12 ± 0.17 in AA group followed by 0.09 ± 0.14 in AAB group. Dendrogram derived based on UPGMA method also grouped AA cultivars into two different clusters and separated them from the wild Calcutta 4 (AA) indicating the involvement of several Musa acuminata subspecies in the origin and evolution of AA diploids. The current work revealed the status of genetic diversity and population structure among Musa genome groups implying the need of effective conservation of diploid M. acuminata (AA) group.

Key words: Banana, genetic diversity, Musa, random amplified polymorphic (RAPD), population structure.

International Journal of Plant Breeding and Genetics ISSN: 3167-5891 Vol. 3 (1), pp. 166-176, June, 2016. © International Scholars Journals

Full Length Research Paper

Combined use of parentage analysis and phenotypic assessment to evaluate the performances of cocoa (Theobroma cacao L.) varieties in farmers’ field

Olivier Sounigo^1,2, Fidèle Nsouga², Olivier Fouet³, Claire Lanaud³, Ives Bruno Efombagn Mousseni²*

¹CIRAD, UR Bioagresseurs, BP 2572 Elig-Essono, Yaoundé, Cameroun.

²IRAD P0 Box 2123, Yaoundé, Cameroun.

³CIRAD, UMR AGAP, TA A108/3, Avenue Agropolis, 34398 Montpellier, France.

Corresponding author. E-mail: [email protected]

Accepted 19 June, 2016

Abstract

The genetic diversity of a cocoa population composed of 264 adult trees grown in anon farm plantation was assessed using 125 microsatellite markers to understand the relationship between the origin of the cultivated material and its agronomic features in the field. Analysis using a Bayesian model-based method allowed us to divide the cocoa trees into eight sub-populations (clusters) totaling 456 alleles with a coefficient of differentiation, F_ST = 0.1. Genealogical classes were generated within the entire population, and allowed to clearly identify 157 cocoa trees (59.46% of the total population) as derived from crosses between the two parental clones represented in bi-clonal seed-gardens, and were considered as true improved cocoa varieties while the genetic origin of 107 cocoa trees failed to be clearly identified. The parentage analysis carried out on the 157 trees identified as true F1-hybrids revealed that they belong to seven full-sib different progenies, derived from seven different bi-clonal seed-gardens. A comparison of the agronomical performances of three of the identified full-seed progenies showed differences for traits such as yield and susceptibility to pod rot caused by Phytophthora megakarya.

Keywords: Cacao, genetic structure, full-sib progenies, parentage analysis, morphological evaluation.

International Journal of Plant Breeding and Genetics ISSN 5756-2145 Vol.  2 (4) pp. 161-165, April, 2015. © International Scholars Journals

Full Length Research Paper

Reaction of transgenic Bt cowpea lines and their mixtures under field conditions

*Mohammed Anwar, Ahmed Nassar and Muhammed V. Ali

Department of Plant Science, Faculty of Agriculture, Federal University of Agriculture, Abeokuta, Abeokuta, Nigeria.

E-mail: [email protected] 

Accepted 12 March, 2015

Abstract 

Transgenic cowpeas are those genetically engineered with Cry1Ab gene for protection against the lepidopteran pest Maruca vitrata that could inflict upto 80% yield loss in severe infestation. Two transgenic events TCL-709 and TCL-711 were crossed to three non -transgenic lines IT97K-499-35, IT93K-693-2 and IT86D-1010 to generate six set of F₁ hybrids. The study was designed and conducted to evaluate the performance of transgenic cowpeas and hybrids derived from them under natural field conditions. The transgenics, non-transgenics and the hybrids were planted with intra and inter-row spacing of 30 and 75 cm respectively in a completely Randomized Block Design during the 2012 cowpea growing season at Confined Field Trial site of Institute for Agricultural Research of Ahmadu Bello University Samaru-Zaria. The plot sizes consisted of 2 rows of 5 m long. The trial was kept weed-free by constant manual weeding. The various generations of IT97K-499-35 x TCL-709 were infested six times with first instar Maruca larvae at four day interval at flower initiation stage while the remaining crosses were exposed to natural infestation of Maruca. The data were recoreded on various characters and the results revealed that the cowpea lines containing the cry1Ab gene produced enough toxin to kill and inhibit the feeding of Maruca on cowpea plants. The result on infestation of Maruca larvae scored as number of damaged pods per plant gave a clear proof of the achievement of the goal of the genetic transformation of cowpea lines with Cry1Ab gene. As the Cry1Ab gene conferred a high degree of resistance to cowpea pod borer, the transgenic cowpea lines should be used as a precious insect-resistant line to be employed in traditional breeding programs to develop Maruca resistant cowpea varieties.

Key words: Bacillus thuriengiensis, confined field trial, Cry1Ab gene, transgenic cowpea, Maruca vitrata.