Search Results (3)

The hybrid development of pumpkins, utilizing local genetic material, has recently garnered attention in India. This study aimed to evaluate the combining ability, heterosis, and per se performance of pumpkin hybrids for yield-related and biochemical traits. In the present investigation, eight parental lines of pumpkins were hybridized using a half-diallel mating design, resulting in 28 F₁ hybrids (reciprocals not included). The produced F₁ hybrids, parental lines, and a commercial check were assessed in a randomized complete block design with three replications during the summers of 2023 and 2024. The results obtained in the study show that the best performers with the most desirable characteristics were P-7 for total soluble solid, dry matter content, and average fruit weight; P-3 for total carotenoids, number of seeds per fruit, and antioxidant activity; P-2 for yield per plant and flesh thickness; and P-8 for number of fruits per plant. The parent P-5 for fruit number, average fruit weight, and yield per plant; P-2 for flesh thickness and antioxidant activity; P-7 for TSS and dry matter content; P-1 for fruit number; and P-3 for total carotenoids were noted as the best general combiners in terms of the effects of the parental lines on general combining ability. Conversely, the crosses P-2 × P-5 for yield per plant and flesh thickness and P-1 × P-2 for DPPH activity were found to outperform better-parent heterosis and standard heterosis in terms of heterosis and the specific combining ability magnitude of the F₁ hybrids. Thus, the findings of this study reveal that these hybrids possess strong potential for commercial cultivation, contributing to the development of high-yielding and nutritionally superior pumpkin hybrids after being tested in various seasons and locations. Full article

Protected cultivation is a resource-efficient method of crop production, however, at the same time, it is resource intensive. An optimum rate and time of fertilizer application is required in order to maximize crop yield vis-à-vis resource use efficiency. However, these aspects are scarcely studied for tomato under low- and medium-tech greenhouses in Indian humid sub-tropics. In this regard, a two-year study was conducted to assess the effect of four NPK fertilization rates (i.e., 120, 100, 80, and 60% of the recommended dose of fertilizers, RDF) and three fertigation scheduling approaches—fertigation at different stages in different proportions of NPK, along with an additional treatment, i.e., farmers’ practice (soil-based application of recommended NPK) for tomatoes under a naturally ventilated polyhouse. The plant growth attributes, the tomato yield- and quality-related traits, the nutrient (NPK) accumulation by the plants, the water use efficiency (WUE), and economics were studied in response to different fertigation rates and scheduling approaches. These parameters were affected by both the rates of NPK fertilization and their time of application (scheduling) over the different growth stages. Among the different rates and time of fertigation, the recommended dose of fertilizer (100% RDF) (i.e., 300 kg N, 150 kg P₂O₅, and 150 kg K₂O per ha and their scheduling as 15% N, 10% P₂O₅, and 10% K₂O of RDF during 15–45 days after transplanting (P₁); 40% N, 40% P₂O₅, and 40% K₂O of RDF during 47–76 DAT (P₂); 30% N, 40% P₂O₅, and 40% K₂O of RDF during 77–107 DAT (P₃); and 15% N, 10% P₂O₅, and 10% K₂O of RDF during 108–138 DAT (P₄)) was found to be the optimum for fruit yield, WUE, and economics of tomato under protected condition. Full article

On 6 April 2021, a 200 m-long under-construction prestressed concrete bridge failed in the Chitwan District in central Nepal. Two of the four bridge spans collapsed without any notable evidence of dynamic force application. Under-construction bridge failures are sometimes reported and can have a significant impact on the future construction adjustments. Thus, a detailed study of failure mechanisms will be insightful for the structural engineering community. Aiming to document the failure modes and exemplify lessons for improvement, this paper reports the detailed component level failure mechanisms of the bridge using visual inspection, site measurements, finite element modeling, and some forms of non-destructive testing. The chronological failure mechanisms are presented based on the field evidence and juxtaposed with the results of analytical modeling. The sum of findings highlights that the dead load failure, triggered by the settlement of falseworks, is the most critically governing factor that initiated and aggravated the damage scenario. Full article