Prickly pear (Opuntia ficus-indica (L.) Mill. 1768) is cultivated in several dry and semi-dry areas of the world to produce fresh fruit, bioenergy, cosmetics, medicine, and forage. One of the main production constraints is the presence of many seeds within the fruit, which can negatively influence both the fresh-fruit market price and industrial transformation processes. In this study, different gibberellic acid (GA3) concentrations were tested for their ability to produce well-formed and seedless fruits. Different application methods (injection and spraying) and concentrations of GA3 (0, 100, 200, 250, and 500 ppm) combined with floral-bud emasculation were applied to a commercial plantation in southern Italy to evaluate their effects on the weight, length, and diameter of the fruits, total seed number, hard-coated viable seed number, and seed weight per fruit. The results indicated that the application of 500 ppm GA3 sprayed on emasculated floral buds was the most effective method for reducing seed numbers of prickly pear fruits (−46.0%). The injection method resulted in a very low number of seeds (−50.7%) but produced unmarketable fruit. Observed trends suggest the need to investigate the impact of higher GA3 concentrations and the applicability of a maximum threshold. Further studies are needed to increase our understanding of the physiological effects of the gibberellic acid pathway through productive tissue in terms of organoleptic and fruit quality.

The continuous increase in the world population and the associated food demands in the wake of climate change are pushing for the development and cultivation of climate-resilient crops that are able to efficiently use natural resources. Proso millet (Panicum miliaceum L.) might be a promising candidate crop thanks to its heat stress resistance and its limited water demand. To date, one of the most important strategies to increase grain yield and to improve other agronomic important traits is through an efficient breeding program based on a wide genetic variability of parental germplasm. In this study, we evaluated the agronomical traits of a world collection of 80 P. miliaceum accessions. The entire collection was evaluated over a 2 year field experiment under Mediterranean pedoclimatic conditions, which exhibited a wide range of variability for plant height (25–111 cm), grain yield (842–3125 kg ha−1), total dry biomass (2767–10,627 kg ha−1), harvest index (HI; 0.25–0.35), Growing Degree Days (GDDs; 581–899), and days to maturity (80–111 d). A non-parametric multivariate analysis of variance (Np-MANOVA) analysis indicated that GDDs to flowering, grain yield, total dry biomass, days to maturity, plant height, and seed yield per plant were useful parameters to differentiate the germplasm accessions. High heritability (>0.60) was observed in both years for plant height, leaf number, basal tiller, seed yield per plant, 100-seed weight, GDDs to flowering, and days to maturity. Grain yield, total dry biomass, and HI reported moderate heritability (0.30–0.60). The findings reported in the present study may provide valuable information that could support researchers in breeding programs to develop high grain-yielding accessions.

In recent years, biochar has generated global interest in the areas of sustainable agriculture and climate adaptation. The main positive effects of biochar were observed to be the most remarkable when nutrient-rich feedstock was used as the initial pyrolysis material (i.e., anaerobic digestate). In this study, the influence of solid anaerobic digestate and biochar that was produced by the slow pyrolysis of solid digestate was evaluated by comparing the differences in the crop growth performances of Pelargonium graveolens. The experiment was conducted in a greenhouse while using three different growth media (i.e., solid digestate, biochar, and vermiculite). The results indicated that: (i) the pyrolysis of solid digestate caused a reduction in the bulk density (−52%) and an increase in the pH (+16%) and electrical conductivity (+9.5%) in the derived biochar; (ii) the best crop performances (number of leaves, number of total branches, and plant dry weight) were found using biochar, particularly for plant dry weight (+11.4%) and essential oil content (+9.4%); (iii) the essential oil quality was slightly affected by the growth media; however, the main chemical components were found within the acceptable range that was set by international standard trade; and, iv) biochar induced the presence of leaf chlorosis in Pelargonium graveolens.

In many African countries, such as Madagascar, a large part of the population is currently estimated to be undernourished, and self-subsistence agriculture represents the primary source of food available for the family. Smallholder farmers cultivate crops with limited agricultural input and use old landraces or obsolete hybrid varieties, with a total country-wide production that is far from being able to sustain the national food demand. In this study, we have developed two maize composite cross populations (CCPs) of different kernel colors, through a selection process among 30 half-sib lines, chosen both for their agronomic performance and their environmental adaptability to a Malagasy farm context. The best half-sib lines, identified through field tests, were clustered as a parental group for open-pollinated crosses. The new CCP created, after two years of seed multiplication in an open field, showed promising yields compared with the hybrids, parental varieties, and local landraces, with average values of 2.7 t/ha for the white CCP and 3.5 t/ha for the yellow one. The seeds produced were then distributed among 15 local farmers to begin a participatory breeding program. Our approach represents an innovative step to improve and stabilize maize yields, employing populations adapted to the cultivation environment and able to cope with different stresses, thereby helping farmers’ life conditions.

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