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Since phosphorus (P) is lower in agricultural areas with acid sandy soil, it runs out in different parts of crop plants after harvesting. To boost growth and development in the next cropping system, only overuse of inorganic phosphate fertilizers can adversely affect agricultural sustainability. Phosphate-solubilizing fungi like Candida tropicalis play a role in plant P nutrition through soil P dynamics and growth hormones. Three PSF isolates (Sw01, Pu02, and Pu04) from bulk soil of fresh corn were tested for optimal media and incubation times. The results showed that Sw01 produced the highest population of 593.33×10⁸CFU L⁻¹ when cultured in TB media after five days. These PSFs were used to investigate the potential of C. tropicalis on yield components, chlorophyll pigments, and nutritional value of vegetable soybean cv. Chiang Mai 84-2. The result demonstrated that applying 50% inorganic fertilizer mixed with C. tropicalis enhanced leaf area, root length at the vegetative stage, and chlorophyll a and total chlorophyll contents at the flowering and harvest stage. This application increased pod fresh weight to 11,214 kg ha⁻¹, with an average of 28 pods plant⁻¹ and 47.50 seeds plant⁻¹ compared to fertilizer managements.

Agricultural water rationalization expressed in irrigating the plants below their requirements became a significant strategy in crop water management. However, reduction in crop productivity under low water supply is realized. Therefore, the current study aimed to diminish sunflower yield losses associated with deficit irrigation using salicylic acid (SA). During two seasons of 2019 and 2020 at El Nubaria region, El Behaira Governorate, Egypt, combinations of three irrigation regimes (100, 85 and 70% of crop evapotranspiration, denoted WR100%, WR85%, and WR70%, respectively), and three levels of SA (0.0, 0.5, and 1 mM. abbreviated as SA0.0, SA0.5, and SA1.0, respectively) on sunflower plants performance were evaluated. Treatments were arranged in a strip–plot design with three replicates. Findings revealed that treated sunflower plants with WR100% × SA1.0 contained the highest amounts of total chlorophyll and carotenoids as well as the lowest proline content. Seed yield of WR100% × SA1.0 treatment was higher than that of WR70% × SA0.0 by 109.7% in the first season and 125.9% in the second one. As averages of the two seasons, SA0.5 and SA1.0 lowered the reductions in seed yield from 21.0% to 15.8 and 14.4% as well as 46.2% to 40.8 and 40.1% under WR85% and WR70%, respectively, compared to the farmer common practice (WR100% × SA0.0). WR100% × SA1.0 for iodine value as well as WR100% × SA1.0 and WR100% × SA0.5 for seed oil % were recorded the highest. Application of WR100% × SA1.0 and WR100% × SA0.5 were the effective combinations for ameliorating water use efficiency. In conclusion, involving salicylic acid in irrigation programs of sunflower became a decisive action to save water and alleviate the yield losses resulting from drought stress.

Food security and the agricultural economy are both dependent on the temporal stability of crop yields. To this end, increasing crop diversity has been suggested as a means to stabilize agricultural yields amidst an ongoing decrease in cropping system diversity across the world. Although diversity confers stability in many natural ecosystems, in agricultural systems the relationship between crop diversity and yield stability is not yet well resolved across spatial scales. Here, we leveraged crop area, production, and price data from 1981 to 2020 to assess the relationship between crop diversity and the stability of both economic and caloric yields at the state level within the USA. We found that, after controlling for climatic instability and differences in irrigated area, crop diversity was positively associated with economic yield stability but negatively associated with caloric yield stability. Further, we found that crops with a propensity for increasing economic yield stability but reducing caloric yield stability were often found in the most diverse states. We propose that price responses to changes in production for high-value crops underly the positive relationship between diversity and economic yield stability. In contrast, spatial concentration of calorie-dense crops in low-diversity states contributes to the negative relationship between diversity and caloric yield stability. Our results suggest that the relationship between crop diversity and yield stability is not universal, but instead dependent on the spatial scale in question and the stability metric of interest.

Background In regional wheat trials, when short-stem wheat varieties and high-stem wheat varieties are planted adjacent to each other in small plots, changes in their marginal plot environment can lead to bias in yield evaluation. Currently, there is no relevant research revealing the degree of their mutual influence. Results In a regional wheat experiment, when high-stem wheat varieties and short-stem wheat varieties were planted adjacent to one another, there was no significant change in soil temperature or humidity in the high-stem wheat variety experimental plot from November to May compared to the control plot, while the soil humidity in the short-stem wheat variety experimental plot was greater than that in the control plot. In May, the soil temperature of the short-stem wheat varieties in the experimental plot was lower than that in the control plot. Illumination of the wheat canopy in the high-stem wheat variety experimental plot had a significant positive effect in April and May, while illumination of the wheat canopy in the short-stem wheat variety experimental plot had a negative effect. The chlorophyll fluorescence parameters of flag leaves in the high-stem wheat variety experimental plots showed an overall increasing trend, while the chlorophyll fluorescence parameters of flag leaves in the experimental plots of short-stem wheat varieties showed a decreasing trend. The analysis of the economic yield, biological yield, and yield factors in each experimental plot revealed that the marginal effects of the economic yield and 1000-grain weight were particularly significant and manifested as positive effects in the high-stem wheat variety experimental plot and as negative effects in the short-stem wheat variety experimental plot. The economic yield of the high-stem wheat variety experimental plot was significantly greater than that of the control plot, the economic yield of the short-stem wheat variety experimental plot was significantly lower than that of the control plot, and the economic yield of the high-stem experimental plot was significantly greater than that of the short-stem experimental plot. When the yield of the control plot of the high-stem wheat varieties was compared to that of the control plot of the short-stem wheat varieties, the yield of the control plot of the short-stem wheat varieties was significantly greater than that of the control plot of the high-stem wheat varieties. Conclusions Based on these findings, it is concluded that plots with high-stem and short-stem wheat varieties are adjacent in regional wheat trials, the plots of high-stem wheat varieties are subject to marginal positive effects, resulting in a significant increase in economic yield; the plots of short-stem wheat varieties are subject to marginal negative effects, resulting in a decrease in economic yield. This study reveals the mutual influence mechanism of environment and yield with adjacent planting of high-stem and short-stem wheat varieties in regional wheat trials, providing a useful reference and guidance for optimizing the layout of regional wheat trials.

Nitrogen (N) is an important macronutrient and is comprehensively involved in the synthesis of secondary metabolites. However, the interaction between N supply and crop yield and the accumulation of effective constituents in an N-sensitive medicinal plant Panax notoginseng (Burkill) F. H. Chen is not completely known. Morphological traits, N use and allocation, photosynthetic capacity and saponins accumulation were evaluated in two- and three-year-old P. notoginseng grown under different N regimes. The number and length of fibrous root, total root length and root volume were reduced with the increase of N supply. The accumulation of leaf and stem biomass (above-ground) were enhanced with increasing N supply, and LN-grown plants had the lowest root biomass. Above-ground biomass was closely correlated with N content, and the relationship between root biomass and N content was negatives in P. notoginseng ( r = −0.92). N use efficiency-related parameters, NUE (N use efficiency, etc .), N C (N content in carboxylation system component) and P n (the net photosynthetic rate) were reduced in HN-grown P. notoginseng . SLN (specific leaf N), Chl (chlorophyll), N L (N content in light capture component) increased with an increase in N application. Interestingly, root biomass was positively correlated with NUE, yield and P n . Above-ground biomass was close negatively correlated with photosynthetic N use efficiency (PNUE). Saponins content was positively correlated with NUE and P n . Additionally, HN improved the root yield of per plant compared with LN, but reduced the accumulation of saponins, and the lowest yield of saponins per unit area (35.71 kg·hm −2 ) was recorded in HN-grown plants. HN-grown medicinal plants could inhibit the accumulation of root biomass by reducing N use and photosynthetic capacity, and HN-induced decrease in the accumulation of saponins (C-containing metabolites) might be closely related to the decline in N efficiency and photosynthetic capacity. Overall, N excess reduces the yield of root and C-containing secondary metabolites (active ingredient) in N-sensitive medicinal species such as P. notoginseng .

In this work, we study the model of a fish species growing logistically exploited by a fishing fleet in a heterogeneous environment. The environment is made up of a network of fishing patches connected by fish migrations taking place on a fast time scale. We are interested in the maximum economic yield (MEY) which corresponds to the maximum profit made by the fishing fleet. We show that the total MEY profit of the fishery made up of all the connected fishing patches can be greater than the sum of the MEY profits of isolated patches in the absence of migration. We study the general case with any number of connected patches then focus on the case of a system composed of two patches. In the latter case, we show that asymmetry in fish migration plays an important role in increasing the total profit at the MEY by connecting patches. We illustrate our results with numerical simulations allowing us to compare the MEY fishery system with connected patches compared to the system with isolated patches.

Tenualosa ilisha is an anadromous fish that can be found in the Bilah River and Barumun River, Labuhanbatu Regency, Indonesia, among other places. T. ilisha is a significant target for fishermen because it has high economic value. However, T. ilisha populations continue to decline due to overfishing. Good management is needed so that the economic value can be utilized sustainably. This study aims to analyze the bioeconomics of T. ilisha in the Labuhanbatu District, Indonesia. The data used in this study was collected from purchases by wholesalers between 2017-2021. The results showed that the maximum sustainable yield (MSY) value was 959.93 kg year-1, and the optimal effort (FMSY) value was 456.82 trips. MSY's profit was 5031.13 USD, and the maximum economic yield (MEY) was 5574.79 USD. Based on the results, it was concluded that the high economic value of T. ilisha would lead to overfishing.

The strategic objectives for fisheries, which are enshrined in international conventions, are to maintain or restore stocks to produce maximum sustainable yield (MSY) and to implement the ecosystem approach, requiring that interactions between species be taken into account and conservation constraints be respected. While the yield and conservation aims are, to some extent, compatible when a fishery for a single species is considered, species interactions entail that MSY for a species depends on the species with which it interacts, and the yield and conservation objectives therefore conflict when an ecosystem approach to fisheries management is required. We applied a conceptual size- and trait-based model to clarify and resolve these issues by determining the fishing pattern that maximizes the total yield of an entire fish community in terms of catch biomass or economic rent under acceptable conservation constraints. Our results indicate that the eradication of large, predatory fish species results in a potential maximum catch at least twice as high as if conservation constraints are imposed. However, such a large catch could only be achieved at a cost of forgone rent; maximum rent extracts less than half of the potential maximum catch mass. When a conservation constraint is applied, catch can be maximized at negligible cost in forgone rent, compared with maximizing rent. Maximization of rent is the objective that comes closest to respecting conservation concerns.

The method of automatically controlling the CO2 concentration in a greenhouse depending on ventilation was examined in order to efficiently improve the productivity of strawberries under the weather conditions in the northern part of Kyushu in Japan. The effects of CO2 enrichment on the yields, fruit Brix, and economic value of the strawberry ‘Sagahonoka’ were investigated. In addition, in order to clarify the physiological response of ‘Sagahonoka’ to the CO2 concentration, the photosynthetic rate, translocation, and photoassimilate distribution rate were measured. It was found that maintaining the CO2 concentrations above 800 μmol mol−1 and 400 μmol mol−1 during no ventilation and ventilation, respectively, resulted in 25% increases in marketable fruit yields and a 0.2–1.2% higher fruit Brix compared to control, which was kept in 400 μmol mol−1 CO2 or above all day regardless of ventilation. Additionally, the economic value of ‘Sagahonoka’ was increased. The photosynthetic rate of ‘Sagahonoka’ increased linearly up to 800 μmol mol−1 CO2, and high CO2 concentrations affected the distribution for the primary fruit, the most significant sink. It was clarified that CO2 enrichment at 800 μmol mol−1 for ‘Sagahonoka’ was effective in increasing the photosynthetic rate and distribution of photoassimilates to fruits, and the yields of strawberries could be increased efficiently by automatically controlling the CO2 concentration depending on ventilation in a southern region of Japan.

Fisheries can generate substantial economic returns to society if managed with economic targets as the main objective, that is with biomass, catch, and effort levels that correspond to maximum economic yield (MEY), although the move to such targets presents a number of challenges. These are compounded in multispecies fisheries, as it is not possible to achieve all individual targets simultaneously if targets are set on a species-by-species basis. Identifying appropriate targets both conceptually and empirically has also proven challenging, and consequently the implementation of economic targets to real world fisheries have been limited to a small number of data-rich and high-valued fisheries, with reliance on proxy target reference points in other fisheries. Moreover, these application has been limited due to unknowns as to what proxies should be used under different circumstances. Here, we review the alternative ways in which MEY has been estimated and applied in multispecies fisheries. We also review the roles and potential use of proxy target reference points for multispecies MEY in data-limited fisheries, building on Australian’s experience in implementing such a policy.