Agricultural Research最新文献

During the last decades, water distribution around the globe has been affected by climate change. Particularly, in Chile, the last decade has been marked by a mega-drought period, which has severely impacted agriculture. In this scenario, common bean (Phaseolus vulgaris L.) has been seriously affected due to its dependence on irrigation. In this work, we studied how 'Zorzal,' the most sown cultivar in Chile copes with drought stress and the mechanisms used to deal with it. A greenhouse experiment was performed during the 2019–2020 growing season. Plants were subjected to a severe drought stress suspending irrigation at the pre-flowering stage. Photosynthetic parameters, chlorophyll concentration, relative leaf water content (RWC) and lipid peroxidation were analyzed at 7 and 21 days after water suspension, yield was analyzed at the end of the growing season, and those parameters were compared to a susceptible cultivar of the same gene pool ‘Arroz Tuscola.’ ‘Zorzal’ stood out for having diverse treats associated with drought tolerance, as maintaining stable RWC during drought stress, a better reactive oxygen species scavenging system than ‘Arroz Tuscola,’ and stable root biomass during the drought condition. However, seed production was significantly reduced. Our results evidence that ‘Zorzal,’ the most widely cultivated cultivar of common bean in Chile, has good physiological and anatomical treats for plant survivance under drought stress conditions. However, our study suggests that these characteristics may not be enough to maintain a stable seed production.

The tomato plant (Solanum lycopersicum L.) demands more water than other vegetables. However, water availability has become a limiting factor worldwide due to climate change. Thus, it is essential to explore the genetic variability of species to develop genotypes with satisfactory yields under low water availability. In this context, the objective of this study was to identify water-deficit-tolerant plants within the genetic variability of tomatoes and to select drought-tolerant genotypes from the second generation of the first backcross (F₂BC₁). For this, seven wild accessions, three S. lycopersicum var. cerasiforme accessions, and six commercial cultivars were tested. Moreover, intra- and interspecific crosses were performed and from the crosses S. lycopersicum × S. pennellii, two F₂BC₁ populations were obtained. Three experiments were conducted where the genotypes were subjected to water deficit and physiological and growth parameters. The commercial tomatoes were the most susceptible to water deficit. Among the tested cerasiform varieties, the RVC 66 accession was the least affected by the reduced water supply. The LA 716 accession (S. pennellii) had the highest tolerance to water deficit, followed by ‘LA 1401’ (S. galapagense) and ‘LA 1967’ (S. chilense). The LA 716 accession was the most promising to introgress drought tolerance-related genes in the commercial tomatoes compared to the intraspecific crosses. In addition, crossing between ‘LA 716’ and the commercial tomatoes ‘Clara’ and ‘Redenção’ allowed the development and selection of drought-tolerant F₂BC₁ genotypes.

The use of green and eco-friendly materials is growing in agriculture day by day. Nanoparticles (NPs) and plant growth regulators (PGRs) are the most applied agents in food and fruit preservation. This study is aimed to evaluate the effects of AgNPs, SiNPs, epibrassinolide, and methyl jasmonate on the several postharvest physiological traits and decay of M. domestica var. Fuji (apple) fruits at ambient conditions. Results showed that antioxidant-related traits including total phenols, catalase, and peroxidase activity increased in NPs and PGRs-treated fruits. Total protein content was also found to be higher than control. Total sugar content and pH value were observed to be low in NPs and PGRs-treated fruits, while titratable acidity was higher than control. Decay, one of the important indicators of postharvest quality, was highly lower in both NPs and PGRs-treated fruits, improving its shelf life during storage. The results of the current study revealed that both NPs and PGRs can be used as an alternative tool in fruit preservation.

Cutting’s rooting and budding are one of the main constraints for the domestication and cultivation of G. africanum and G. buchholzianum. The effects of exogenous indol-3-acetic acid (IAA) and indol-3-butyric acid (IBA) on rooting and budding from cuttings of both lianas were studied. Fresh cuttings of both lianas were soaked for 12 h in DKW mineral complex supplemented with varying concentrations (0 mg L⁻¹, 50, mg L⁻¹ 100 mg L⁻¹, 150 mg L⁻¹, and 200 mg L⁻¹) of IAA and IBA. The above-treated cuttings were sown in propagators and monitored for eight weeks. Auxins’ treatment of cuttings significantly improves roots and bud’s expression of cuttings from both liana species. Compared to their respective controls (5.11 ± 0.74% and 7.06 ± 1.60%), rooting response of cuttings was significantly improved in G. africanum (IAA:23.11 ± 3.54% P_v = 0.039; IBA:37.28 ± 6.47%, Pv = 0.076) and G. buchholzianum (IAA:32.42 ± 4.31%, Pv = 0.009; AIB: 30.16 ± 4.08%, Pv = 0.021). Best rooting (59.22%) and budding (57.77%) response was obtained respectively with IBA 150 mg L⁻¹ and 100 mg/L⁻¹ in G. africanum. IBA allowed the development of the longest root (9.2 cm) and highest number of roots (12 roots/cutting) respectively with 100 mgL⁻¹ and 150 mg L⁻¹. Hence, exogenous IBA (100 mg L⁻¹ and 150 mg L⁻¹) and IAA (100 mg L⁻¹) are suitable for root induction and expression in both lianas. However, 100 mg L⁻¹ IBA appeared to be efficient in stimulating budding in studied lianas. This technical pathway is useful for planting material production from G. africanum and G. buchholzianum cuttings. The obtained planting material were found suitable for farm establishment.

Penicillium digitatum and Botrytis cinerea are some of the most important post-harvest pathogenic fungi infecting vegetables and fruits. This study is aimed to assess the antifungal potency of chlorine dioxide (ClO₂) and peracetic acid (PAA) by examining the growth of P. digitatum and B. cinerea on inoculated potato-dextrose-agar medium (PDA), sweet orange and strawberry fruits under in vitro and storehouse conditions. Furthermore, the antifungal efficacy of ClO₂ and PPA was compared with four commercial fungicides namely Thiabendazole, Imazalil, Cyprodinil and Thiophanate-methyl (1000 mg/L). The results indicated that the antifungal activity of ClO₂ and PAA under both in vivo and in vitro conditions were similar to the chemical fungicides. At lower concentration, ClO₂ was more active than PAA. The radial growth of pathogenic fungi in PDA medium was completely inhibited by 100 ppm ClO₂ and 750–900 ppm PAA. Under the storehouse condition, application of 400 ppm ClO₂ and 1050 ppm PAA completely inhibited the test fungi on orange and strawberry fruits. No significant difference was observed in the total sugar content of the fruits following application of the test compounds at these concentrations. This study concludes that ClO₂ and PAA can be used as viable substitutes for chemical fungicides for the management of P. digitatum and B. cinerea in sweet orange and strawberry fruits.

Socio-economic factors can influence decisions and the intensity of management practices, which when appropriately considered could bridge yield gaps. The study aimed to investigate factors affecting maize (Zea mays L.) production in a smallholder crop-livestock system. Social and management analyses were performed to ascertain the factors influencing maize productivity using interviews and questionnaires. The study was conducted in two main maize-producing regions of Eswatini, the Highveld at Mankayane and Middleveld at Luve. Additionally, on-farm trials were established for two cropping seasons to evaluate maize response to three fertiliser regimes: cattle manure only, cattle manure plus inorganic fertiliser, and inorganic fertiliser only and lastly to determine the most economic fertiliser regime. Each fertiliser regime was replicated six times. Weed biomass and maize yield were collected from a 5 m × 1 m quadrat. Moreover, economic analysis for each fertiliser regime was performed using partial budgets comprising fertiliser and weed management costs. The social and management analyses showed that maize yield was strongly associated with household size (p < 0.05), land area cultivated (p < 0.05) and herbicide application timing (p < 0.05) indicating the effect of these factors on yield. On-farm trials revealed that the inorganic fertiliser only regime resulted in a significantly (p < 0.05) higher maize yield compared to manure only and manure plus inorganic fertiliser regimes in both study areas. Weed biomass was significantly (p < 0.05) lower in the inorganic fertiliser only regime at Mankayane compared to the manure only and manure plus inorganic fertiliser at both localities. The economic analysis showed that the manure only fertiliser regime had low costs that vary and high net benefits indicating that manure has the potential to improve soil conditions, reduce environmental impacts, and increase profits.

Low nitrogen use efficiency (NUE) in corn production leads to reduced harvest and substantial nitrogen (N) losses, adversely impacting environment and agricultural sustainability goals. Controlled release of N fertilizers can improve NUE by controlling the release of N from fertilizer granules, extending N availability to crops, and reducing N loss to the environment. Biochar-based controlled-release N fertilizers (BCRNFs) are a new concept to address the N loss problem and increase yield. In this research, different BCRNFs were developed by impregnating ammonium sulphate (AS) into biochar (BC) and mixing with bentonite (Be), biosolid (BS), rice starch (RS), and bioasphalt (BA) in a different ratio to formulate three new BCRNFs— S1: 40% AS + 55% BC + 5% RS; S2: 50% AS + 15% BC + 15% BS + 20% RS; and S3: 15% AS + 30% BC + 10% Be + 45% BA. Dry pellets of S1 and S2 were coated with 5 wt% poly-lactic acid solution, while pellets of S3 were not coated. The release pattern of N from the BCRNFs was studied in water. The cumulative release of NH₄⁺–N from S1, S2, and S3 was significantly slower than that from AS. The release time of 80% N from S3 was extended up to 30 h. The greenhouse evaluation of BCRNFs consisted of six treatments: control (no N), non-BC commercial controlled-release fertilizer (CCRF), AS, S1, S2, and S3. S1, S2, and S3 corn yields were 196.4%, 209.6%, and 135.7%, respectively, greater than the control treatment (p ≤ 0.05, Tukey’s test). S2 yielded 13.5% and 28.8% more than the non-BC controlled-release fertilizer and AS, respectively. The study demonstrated that BCRNFs coated with poly-lactic acids extend N release duration, boost yield, and reduce N loss in leachate collected in the greenhouse trial of the BCRNFs. Biochar-based BCRNFs have a good prospect for corn production.

Deficit irrigation is known as an effective method for alleviation of drought impacts on crop yield. It also saves a large amount of irrigation water without having a negative impact on yield. Considering the relationship between water consumption and the amount of energy consumed, the evaluation of water productivity (WP) and energy productivity (EP) seems essential to develop a suitable method for efficient use of water for agriculture in the arid regions with limited water resources. Therefore, in this study, it was attempted to investigate WP and EP, some nutritional traits and stress indices for silage maize and silage sorghum in a loamy sandy soil using a drip tape irrigation system. For this purpose, a field experiment was performed using a randomized complete block split-plot design with three replications under three irrigation levels of I1: 100% (conventional), I2: 80%, and I3: 60% of the crop evapotranspiration (ETc), and four cultivars of sorghum and maize were planted as the main and split plots. The irrigation scheduling was done using a reference crop evapotranspiration (ETo) calculator (Penman–Monteith equation) and AquaCrop simulation model. The results showed that the amount of irrigation water had a significant effect on fodder and dry yield, WP and EP (p < 0.01). The values of fresh and dry yields and WP for silage maize were 61.23 tons/ha, 18.91 tons/ha and 10.73 kg/m³, respectively. However, for silage sorghum, with relatively lower water requirements, these values were much higher (103.84 tons/ha, 30.00 tons/ha and 19.82 kg/m³, respectively). The maximum WP and EP for sorghum and maize were obtained in I3 and I1 treatments, respectively. It was also found that the nutritional traits, including dry matter (DM) and crude protein (CP), were affected by crop type (sorghum and maize) and deficit irrigation levels. Hence, the maximum DM (31.72%) and CP (9.607%) were observed for Speedfeed sorghum cultivar under I1 irrigation level, the maximum ash (9.86) was reported for Speedfeed sorghum cultivar under I3 irrigation level, the maximum neutral detergent fiber (NDF) (74.47%) was obtained for Maxima maize cultivar under I1 irrigation level, and the maximum acid detergent fiber (ADF) (39.183%) was achieved for Pegah sorghum cultivar under I1 irrigation level. According to the results, it was concluded that it would be wise to replace sorghum with maize in order to achieve higher WP in arid regions.

Changing climate is one of the main factors affecting to decline food production because crop growth is sensitive to climatic changes. In this study, DSSAT and APSIM models were calibrated and validated at 15 different locations of the Kangsabati river basin and compared based on three output parameters for three famous variety, viz. Swarna, Lalat, and MTU 1010 to identify which one was the most accurate in reproducing rainfed rice yield in the research location. The results suggest that DSSAT model can simulate rice crop growth and yield better than APSIM model in this region. In terms of rice yield, Swarna, a long-duration rice variety, had a greater RMSE (144.63 kg ha⁻¹) than the short-duration rice variety Lalat and MTU 1010. However, the DSSAT model performed better than the APSIM model in modeling rainfed rice crop growth and yield (r² > 0.86 and greater ME). Bias-corrected RCM (HadGEM3-RA) have been linked to the DSSAT model to analyze yield changes of three popular rice varieties (Swarna, Lalat, and MTU 1010) for future climate scenario (2030s & 2040s). The average decrease in rice yield of Swarna is projected to be around 7% in 2030s and 9% in 2040s, and under RCP 8.5, average decrease in rice yield of Swarna is projected to be 12.8% (2030s) and 15.4% (2040s), which is much higher than production of Lalat and MTU 1010 in both the cases. In conclusion, DSSAT might be a helpful tool for determining the effects of management techniques and climate change on various rice varieties.

The availability of information regarding breeding and molecular aspects of African marigold (Tagetes erecta L.) is rare, and a very few hybrids have been developed for this economically viable crop. A study was conducted using 13 parental genotypes (3 male sterile lines and 10 testers) of African marigold to develop 30 F₁ hybrids, and the true hybrids we evaluated based on phenotypic and marker-based genotypic data. Analysis of variance revealed significant diversity among the parental lines for different growth and flower traits. Fourteen SSR markers were used to test the purity of selected F_1s, out of which two markers (TE57, T93B) showed polymorphism in the parental lines and cross combinations, with 2–5 alleles. The markers, TE57 and T93B revealed polymorphism information content (PIC) of 0.345 and 0.543 (mean 0.444), respectively, and detected a heterozygosity mean value of 0.528 in all, indicating the efficacy of microsatellite markers in discriminating the hybrids. The phenotypic data revealed significant difference in means for both quantitative and qualitative traits between the parents and the hybrids, in support of the molecular outcomes pertaining that hybrids detected through microsatellite markers were pure F_1s. The study identified a set of compatible cross combinations that can be used to develop highly heterotic hybrid combinations with different growth and flowering characteristics.