ABSTRACT In semi-arid regions, where water availability and soil fertility limit agricultural production, intercropping vegetables represent a sustainable strategy, increasing resource use efficiency. However, adopting this system requires understanding its interactions and advantages compared to monoculture. In this sense, this study evaluated the agro-bioeconomic efficiency of intercropping beet and coriander with lettuce in succession, as function of equitable amounts of Merremia aegyptia and Calotropis procera, under different population densities of leafy crops (coriander and lettuce), in semi-arid environment. Two field experiments were conducted (2023 and 2024) at the Rafael Fernandes Experimental Farm, Universidade Federal Rural do Semi-Árido, Lagoinha, Mossoró, RN, Brazil, with four amounts of green manures: 25, 45, 65, and 85 t∙ha-1 in four planting densities of the leafy vegetables: 40, 60, 80, and 100% of the recommended densities in their monocroppings (RDM). The intercropping system outperformed monocropping when 85 t∙ha-1 of M. aegyptia and C. procera biomass was applied, combined with 100% of the RDM, achieving a land equivalent ratio of 2.36 and a productive efficiency index of 0.98. Beet was the dominant crop (aggressivity of 0.23). The increasing amounts of green manures and planting densities favored the competitiveness of coriander and lettuce. Agrobiological efficiency resulted in a 10 intercropping advantage, which translated into significant economic gains, with a net income of BRL 168,600.97∙ha-1 and a profit margin of 80.18%. These results demonstrated that proper management of treatment-factors optimizes the agro-bioeconomic efficiency of beet and coriander intercropping with lettuce in succession, highlighting its potential as a sustainable and diversified model.
ABSTRACT Rising temperatures resulting from climate change present a significant limitation to lima bean (Phaseolus lunatus L.) production, especially in hot and semiarid regions. This study evaluated lima bean genotypes under elevated-temperature conditions to identify heat-adapted lines based on vegetative, physiological, and yield-related traits. Measurements included vegetative growth parameters, gas exchange, photosystem II quantum efficiency, photosynthetic pigments, agronomic traits, and grain yield across 16 genotypes, encompassing both improved lines and landrace varieties. Significant differences were observed among genotypes for all evaluated characteristics, demonstrating considerable genetic variability. Lines H25-64, H94-31, and H25-54 exhibited superior physiological performance, as indicated by higher photosynthetic efficiency and favorable agronomic traits under elevated temperatures. Notably, line H81-32 displayed low growth and physiological performance but achieved the highest grain yield and hundred-grain weight, suggesting efficient allocation of photoassimilates to reproductive sinks. In contrast, lines H25-56 and H25-67 demonstrated high CO2 assimilation and stomatal conductance, yet this physiological advantage did not translate into increased grain yield. Landrace varieties exhibited traits linked to rusticity and morphological adaptation, such as larger pod dimensions, underscoring their value as sources of adaptive alleles. Multivariate analyses revealed that productivity under elevated temperatures is more closely associated with physiological efficiency than with vegetative biomass accumulation. The identified lines constitute promising parental materials for breeding programs targeting the development of heat-tolerant lima bean cultivars suited to warming environments, thereby supporting the sustainability of production systems under climate change.
ABSTRACT Wild common bean accessions represent an important source of genetic variability for improving biological nitrogen fixation (BNF). The aims of this study were to estimate genetic parameters of lines developed under rhizobial inoculation conditions, obtained by backcross between an elite line and a wild accession, and to select high-yielding carioca common bean lines adapted to these conditions. A total of 95 lines derived from a cross between the elite line CNFC 10762 and the wild accession G2k3499A, followed by one backcross to the elite parent, were evaluated. The lines and three check genotypes were evaluated in the 2019 and 2020 winter crop seasons in Santo Antônio de Goiás, GO, Brazil, under BNF-based systems (rhizobial inoculation and absence of mineral nitrogen) using a randomized block design with three replications. Yield, grain appearance, and 100-seed weight were evaluated. Genetic variability was observed among lines, with some exceeding the CNFC 10762 line (1,877 kg•ha-1) and the Pérola cultivar (1,724 kg•ha-1). Heritability estimates were 59% for yield, 78% for 100-seed weight, and 80% for grain appearance, indicating favorable conditions for selection. Notable gains were achieved through simultaneous selection of the best lines for the traits evaluated (6.7% for yield, 15.4% for grain appearance, and 1.5% for 100-seed weight). Six superior lines combining high grain yield (1,835–2,147 kg•ha-1), favorable grain appearance (1.2–1.0), and 100-seed weight (21.1–22.6 g) were identified, confirming the potential of wild germplasm to broaden the genetic base and contribute to developing carioca common bean cultivars better adapted to BNF.
ABSTRACT Industrial seed treatment protects soybean seeds against pests and diseases, but prolonged storage causes progressive physiological quality loss driven by phytotoxicity from neonicotinoid insecticides. To our knowledge, no prior research has evaluated whether stratified application, by applying components in ordered layers, reduces phytotoxicity while maintaining seed quality during storage. We evaluated 10 treatment processes combining fungicide, insecticides, polymer, and finishing powder in stratified or simultaneous sequences on soybean seed physiological quality, stored for 135 days at 20°C. A completely randomized 10 × 4 factorial design (10 processes × four storage periods: 0, 45, 90, and 135 days) with four replications was used. Physiological quality was assessed through germination in paper roll plus vermiculite, seedling emergence, accelerated aging, and modified accelerated aging in substrate. A phytotoxicity index was calculated for each test and analyzed via multivariate analysis and k-means clustering. Simultaneous application of all components (Mix) showed the highest phytotoxicity, reducing germination by 4 percentage points (pp) and vigor by up to 6 pp compared to stratified treatments. Treatments with fungicide in the first stage formed a low-phytotoxicity cluster, while Mix occupied an isolated high-phytotoxicity cluster. Seeds maintained viability for up to 90 days and vigor for up to 45 days under controlled storage. Stratified application, particularly with fungicide and polymer applied first, significantly reduces neonicotinoid phytotoxicity and represents a practical strategy to extend seed safety margins in the soybean seed production chain.
ABSTRACT The presence of fungi in common bean seeds is a recurring problem that compromises the physiological and sanitary quality of the plant material. In this context, antagonistic yeasts are presented as a sustainable alternative, but their application is limited due to their low stability during storage. Then, encapsulated bioformulations that preserve their viability and facilitate their use need to be developed. In this regard, the solution blow spraying technique is an aerohydrodynamic process that promotes the formation of microcapsules and preserves the viability of the encapsulated yeasts. Therefore, this study aimed to evaluate the efficacy of antagonistic yeasts encapsulated by solution blow spraying for controlling fungi in bean seeds. Five yeasts were preliminarily evaluated by in-vitro tests against fungi associated with bean seeds. After selecting the three yeasts to be tested on seeds, they were applied both in fresh and encapsulated form to evaluate their antifungal efficacy and verify that they did not affect seed germination or vigor. The results showed that Meyerozyma guilliermondii,Meyerozyma caribbica, and Yamadazyma mexicana had the greatest antagonistic potential against the evaluated fungi. The application of these yeasts, both fresh and encapsulated, reduced pathogen incidence during storage without affecting seed germination or vigor. These findings support the use of encapsulated antagonistic yeasts as a sustainable strategy for managing fungi in bean seeds.
