Volume 25 (2022)

Leaf stomatal characteristics and key agronomic traits of intersectional peanut f1 hybrids between huayu 665 and arachis paraguariensis

Mon, 31 Mar 2025 00:00:00 GMT

Leaf stomatal characteristics and key agronomic traits of intersectional peanut f1 hybrids between huayu 665 and arachis paraguariensis Han, H.W.; Jiang, C.J.; Xu, C.Y.; Sun, H.J.; Yuan, G.D.; Yu, J.; Wang, C.T. The cultivated peanut is a globally important crop, valued for its oil, food, and feed uses, but has a narrow genetic base. High stress resistance, good-quality and high-yield factors residing in wild species constitute valuable resources for genetic improvement of the peanut cultigen. Some wild species are used as groundcovers, while others utilized as potted plants. Previous studies have focused on compatible wild relatives, but there is a lack of research on the use of incompatible Arachis species. This study aimed to investigate the hybrids produced from a cross between the peanut cultivar Huayu 665 and the incompatible species Arachis paraguariensis, enhancing our understanding of distant hybridization. Ture F1 intersectional hybrids were identified by transposon element marker pairs. Leaf stomata were observed, and main agronomic traits were investigated. The F1 hybrids exhibited significantly fewer large stomata (14.78 per mm²) and longer stomata (26.52 μm) on the abaxial leaf epidermis compared to the female parent, Huayu 665, which had 20.56 per mm² and 16.86 μm, respectively. Compared to Huayu 665, the F1 hybrids exhibited a longer first pair of lateral branches, a wider range of seed set, and more branches, but produced fewer pods per plant. A hybrid with a plant type similar to the female parent was identified. The authenticity of the hybrids was confirmed through molecular, anatomical, and morphological analyses. The hybrid resembling the cultigen may accelerate the utilization of incompatible wild species in peanut breeding. However, its chromosome composition is yet to be determined. To avoid missing true hybrid identification in peanut remote crosses, use of molecular markers distributed across different chromosomes of the wild species was proposed.

PHYLOGENETIC RELATIONSHIP OF MANGROVE SPECIES FOUND IN SRI LANKA BASED ON rbcL GENE SEQUENCE

Sat, 01 Jan 2022 00:00:00 GMT

PHYLOGENETIC RELATIONSHIP OF MANGROVE SPECIES FOUND IN SRI LANKA BASED ON rbcL GENE SEQUENCE Hirimuthugoda, N.Y.; Perera, P.W.A.; Aluthmuhandiram, V.J.; Ishuwara, A. Rashmi; Premakumara, M.M.K.; Lal, P.K. A fertile mangrove community can be seen along the sheltered coastline of Sri Lanka, which is an island in the Indian Ocean. Currently there are 21 species of mangroves that have not yet been genetically classified. Therefore, we intended to perform the Sri Lankan mangrove classification using the rbcL gene marker. Cetyl trimethyl ammonium bromide (CTAB) protocols for DNA extraction from mangroves and Silica extraction method were optimized to extract DNA. All the sequence data obtained in this study were deposited in the NCBI GenBank. Maximum Likelihood and Bayesian phylogenetic trees revealed that, the Sri Lankan mangrove community can be classified genetically under 21 species and the Rhizophora anamalayana plant was identified as a hybrid of two species, R. apiculata and R. mucranata. As far as Ceriops is concerned, the vegetation of the Trincomalee and Puttalam areas seems to be distinctly different. Therefore, need to do more research on this clade in the future. The results of this study can be used as the baseline data for mangrove taxonomy in Sri Lanka and will be supported in future conservation and management actions.

COVID-19 RESTRICTIONS COUNTERFACTUALS: AN OVERVIEW OF POSTHARVEST VALUE CHAIN ACTORS IN NIGERIA

Sat, 01 Jan 2022 00:00:00 GMT

COVID-19 RESTRICTIONS COUNTERFACTUALS: AN OVERVIEW OF POSTHARVEST VALUE CHAIN ACTORS IN NIGERIA Adegbola, J.A.; Owojaiye, O.B.; Ogunremi, O.B.; Aina, O.B.; Achime, K.C.; Lijoka, K.O.; Pessu, P.O. This investigation is borne out of the assumption that postharvest value chain actors experienced disruptions which are fallouts of the COVID-19 restrictions or otherwise. It examines the degree to which changes in livelihood and activities of postharvest value chain actors (farmers, processors, marketers, transporters and consumers) may be attributed to restrictions or the inter-play of intervening factors. The study is cross-sectional and employed the micro approach as its estimation methodology in 18 states across 6 geopolitical zones of the country. Data were obtained through key informant interviews, focus group discussions (FGDs), questionnaires and interview guides. The purposive selection of 16 states with a high incidence of COVID-19 according to the Nigeria Centre for Disease Control (NCDC) and formal restriction along with 2 states with no formal restriction as counterfactual preceded the random selection of 108,000 respondents across 5 categories of postharvest value chain actors from sampling frame provided by Agricultural Development Programme (ADP). Data components were analyzed using both descriptive and inferential statistics. Results showed that the difference in earnings was significant (P ≤ 0.05) in restriction states but not significant (P ≤ 0.05) in counterfactual states; the difference in expenditure on food was not significant (P ≤ 0.05) in both restriction and counterfactual states; the difference in wages paid to work hands was not significant (P ≤ 0.05) in both restriction and the Cross-River States, however, it was in Kogi State; the difference in number of work hands employed was significant (P ≤ 0.05) in restriction States but not significant (P ≤ 0.05) in counterfactual states. This implies that the restrictions affected Nigerians in general irrespective of their restriction statuses because the effects of COVID-19 2restrictions in 34 states and the FCT overshadowed the non-restrictions in 2 states.

QUANTITATIVE AND QUALITATIVE ASPECTS OF CINNAMON (Cinnamomum verum J. Presl) BARK YIELD UNDER MODIFIED PLANTING SYSTEMS

Sat, 01 Jan 2022 00:00:00 GMT

QUANTITATIVE AND QUALITATIVE ASPECTS OF CINNAMON (Cinnamomum verum J. Presl) BARK YIELD UNDER MODIFIED PLANTING SYSTEMS Aluthgamage, H.N.; Fonseka, D.L.C.K.; Benaragama, C.K. Cinnamon is one of the most important export crops in Sri Lanka, which generates a considerable amount of foreign exchange for the country. Therefore, special emphasis should be given to enhancing its production as well as quality. Hence, the study was conducted to evaluate some important quantitative and qualitative aspects of the cinnamon yield, namely, cumulative bark yield, bark dry matter percentage, biological yield, the composition of the biological yield and organoleptic properties under some modified planting systems. Seedlings and vegetatively propagated plants of cinnamon variety Sri Gemunu were planted under three different spatial patterns 1.2×0.6 m with three plants per hill, 1.2×0.4 m with two plants per hill and 1.2×0.2 m with one plant per hill while maintaining equal planting density in a unit area. Plants were harvested according to two harvesting intervals, 6 and 8 months and required measurements were taken. According to the results, the effect of harvesting interval and the interaction effect between planting material and the spatial pattern was significant (p < 0.05) for the cumulative cinnamon bark yield for two years (kg/ha). However, tested factors were not significant (p < 0.05) for the bark dry matter percentage. In contrast, the effects of harvesting interval and planting materials were significant (p < 0.05) for the biological yield of cinnamon plants. When considering the composition of the above ground biological yield of cinnamon plants, the interaction effect between planting material and the spatial pattern was significant (p < 0.05) for the percentages of all components (bark, leaves, stem wood, scrape, immature stems and the un-peelable portion of the mature stems and branches). Vegetatively propagated plants consist of a higher bark oil content and a cinnamaldehyde percentage than seedlings. In contrast, seedlings consist of higher eugenol and cinnamyl acetate percentage than vegetatively propagated plants. When considering benzyl benzoate, β-linalool and β-caryophyllene, an impact from the tested factors was not observed.