Sowing Research Articles

ANALISA KEUANGAN DAN FAKTOR-FAKTOR YANG MEMENGARUHI PRODUKSI BUAH BAWANG MERAH DI KECAMATAN SAPE, KABUPATEN BIMA, NTB

In 2023, Sape Regency will produce 20,081 tons of shallots, up from 19,986 tons in 2020. However, the financing of agricultural businesses is affected by a number of problems at the farmer level. The objectives of this research are as follows: (1) evaluate the financial value and income of shallot farming enterprises in Sape District, Bima Regency, NTB; (2) examine the variables influencing the production of shallot crop in Sape District, Bima Regency. Surveys were used to collect data and analyze it using descriptive analysis. According to research results, during the planting season, the cultivation of shallots in Sape Regency produces a profit of IDR 12,954,665 per cultivated land area or IDR 32,386,662 per hectare. Shallot cultivation has a B/C value of 0.13, more than 0. Therefore, it is useful to develop shallot cultivation in Sape Regency; (2) land area, seed costs, SP36 fertilizer costs, organic fertilizer costs, NPK fertilizer costs, urea fertilizer costs and ZA fertilizer costs are factors influencing shallot agricultural production in Sape District, Bima Regency. In reality, shallot production is (very) influenced by the cost of seeds and insecticides. However, shallot production is not influenced by land area, labor costs, SP36 fertilizer, organic fertilizer, NPK fertilizer, urea fertilizer, ZA fertilizer or other fertilizer costs.

Comparing Pixel-based and Object-based Classification for Mapping Smallholders Rice Field Types Using Planetscope Imagery in Sekampung District, East Lampung, Indonesia

Abstract It is imperative to obtain precise and up-to-date information on the area of rice fields, as the yield of rice is a fundamental indicator of national food security. The mapping of rice fields based on water supply is still limited, particularly in Indonesia, which is characterised by ecological and management diversity. The launch of Planetscope imagery, which offers high temporal and spatial resolution, provides the opportunity to map the types of rice fields occupied by people. The objective of this study is to compare the accuracy of land use mapping using pixel-based (maximum likelihood) and object-based (SNIC segmentation) classification using random forest classification in order to generate a rice field map. The results of the object-based classification showed a total accuracy of 92.8% and a kappa coefficient of 0.82. In contrast, the pixel-based maximum likelihood classification showed an accuracy of 74.34% and a low kappa coefficient of 0.43. The mapping of rice field types relies on remote sensing data and field interview data, with an accuracy of 88.05% and 91.09% in planting season 1 and planting season 2, respectively.

Yield and Quality of Snap Bean (Phaseolus vulgaris L.) Cultivars from Successive Harvests in Spring and Fall Production Seasons in Oklahoma

Numerous studies have evaluated snap bean pod yield and quality at different pod maturities, but only a few have evaluated yield and pod quality across different seasons within the same year or for pods harvested at the same relative maturity successively from the same plants. Hence, the aim of this study was to determine if snap bean yield or pod sugar accumulation differed for pods at the same relative stage of maturity from plants harvested multiple times in spring and fall planting seasons in north central Oklahoma. Nine snap bean cultivars (seven green-podded and two yellow-podded) were field-grown in Spring and Fall 2022 and 2023. Pods were harvested weekly for 3 weeks from the same plants and at the same relative pod development stage. Pod yield and sugar concentration were measured. The total pod yield pooled across seasons and years of ‘Sybaris’ was lower (approximately 4100 kg⋅ha−1) than that of six of the other cultivars, which yielded between 7000 to 8600 kg⋅ha−1. In spring, pod yield increased from 900 to 1300 kg⋅ha−1 in the first harvest to 3500 to 3700 kg⋅ha−1 by the last harvest. In Fall 2022, the yield decreased from 1900 kg⋅ha−1 in the first harvest to 690 kg⋅ha−1 by the last harvest, whereas in Fall 2023 the pod yield remained steady at 2600 to 3000 kg⋅ha−1 at each weekly harvest. The Fall 2022 decrease in yield was likely caused by low temperatures during pod development and a freeze that shortened the harvest season. From the first to the last harvest, the total pod sugar concentration decreased from 145.5 to 107.2 mg⋅g−1, glucose decreased from 48.4 to 33.0 mg⋅g−1, and fructose decreased from 90.7 to 52.0 mg⋅g−1. However, the sucrose concentration increased from 9.2 to 21.9 mg⋅g−1. This decrease in the total and monomeric sugar concentrations, coupled with a disproportionally smaller increase in sucrose, is typical for overly mature snap bean pods, which are considered less desirable because of lower sweetness. Snap bean pods harvested later in the growing season in a successive harvest system at the same relative stage of maturity as earlier harvested pods had sugar concentrations resembling those of overly mature pods, indicating that snap bean plant age may influence the pod sugar concentration.

Динамика ростовых процессов отечественных сортов винограда в разнотипных терруарах

Abstract. The reaction of grape varieties on different edaphoclimatic conditions of various types of terroirs is shown. The research was carried out in the Black Sea viticulture zone of the Krasnodar region (subzone 1), Starotitarovskaya, the Piedmont zone (subzone 1), Goryachiy Klyuch, and the Central Zone (subzone 4), Krasnoselskoye, on technical dark-colored grape varieties Vladimir, Dmitriy and Kurchanskiy of the FSBSI NCFSCHVW breeding. The research year (2024) was characterized by increased solar insolation and a shortage of precipitation during the growing season of grape plants. Different edaphoclimatic conditions of various types of terroirs had different effects on leaf growth processes. The largest leaf size in all studied varieties is formed in the Central agroecological zone of viticulture (subzone 4), Krasnoselskoye. Thenfor the Vladimir and Kurchanskiy varieties, in descending order by leaf size, are the Black Sea zone (subzone 1), Starotitarovskaya, and Piedmont zone (subzone 1), Goryachiy Klyuch, for the Dmitriy variety – Goryachiy Klyuch and Starotitarovskaya. The largest number of leaves per shoot of all varieties was in the Starotitarovskaya (Vladimir 14,3; Dmitry 14.7; Kurchansky 14.3 pcs./shoot), followed by Goryachiy Klyuch (Vladimir 12,7; Dmitry 13.3; Kurchansky 12.3 pcs./shoot) and Krasnoselskoye (Vladimir 10,3; Dmitry 11.3; Kurchansky 12.3 pcs./shoot). The largest number of leaves in the studied varieties in the Starotitarovskaya is determined by milder weather and climatic conditions in the vicinity of the Black and Azov Seas, as well as large estuaries that increase humidity and soften air temperature during the growing season of grape plants. Keywords: leaf surface area, length of shoots, Kurchanskiy, Dmitriy, Vladimir

Research on Crop Planting based on Linear Programming and Multiple Regression Functions

The purpose of this paper is to explore how to optimize crop planting strategies through linear programming and multiple regression functions to help rural revitalization and agricultural modernization. In the study, we consider a variety of factors such as crop planting seasons, plot types, and potential planting risks. By analyzing the crop suitability of different plots and combining constraints such as arable land area limitations and crop rotation requirements, we established a linear programming model with the objective of maximizing economic benefits. At the same time, for the two cases of stagnant and wasteful marketing and selling at a reduced price when the yield exceeds the expectation, binary decision variables are used to find the optimal solution. In addition, this paper uses multiple regression functions to predict the growth rate of sales of major crops such as corn and wheat and predicts the future price growth of edible mushrooms through a gray prediction model (GM (1,1)). In the course of the study, we also discuss the impact of extreme weather due to monsoon climate in the northern region and give the optimal planting scheme based on these perturbation factors. Through gray correlation analysis, this paper further explores the correlation coefficients between planting cost and selling price relative to expected sales volume and combines the principles of complementarity and substitutability to derive the highest yielding planting strategy. Finally, the stability of the model is verified by sensitivity analysis, and its adaptability in other agricultural scenarios is explored.

ANALISIS PEMENUHAN KEBUTUHAN EKONOMI RUMAH TANGGA PETANI KENTANG DI DESA TOSARI KECAMATAN TOSARI KABUPATEN PASURUAN

The selling price of potatoes fluctuated, and the rising production input costs affected income, leading farmers to work in off-farm and non-farm sectors to meet household economic needs. The research aimed to analyze potato farming income as well as total household income and expenditures. The sampling method used purposive sampling, with a total of 60 respondents. This study employed income analysis and descriptive analysis. The results showed that the income from potato farming was Rp13,465,899.12 per planting season. The total household income of the farmers was Rp20,993,565.78 over four months, consisting of on-farm, off-farm, and non-farm income sources. Household expenditures amounted to Rp7,116,555.56, which included food and non-food expenses. Keywords: Farming; Income Analysis; Farmers' Households

Non-destructive measurement of chlorophyll content in Sonchus oleraceus L. (Asteraceae) under variations in cultivation and planting season using digital image analysis

Non-destructive measurement of chlorophyll content in Sonchus oleraceus L. (Asteraceae) under variations in cultivation and planting season using digital image analysis

DEVELOPMENT OF A MECHANICAL EQUIPMENT FOR TRANSPLANTING SUGARCANE (Saccharum spp. Hybrids) SPROUTS

Manual planting of sugarcane (Saccharum spp. Hybrids) in Mexico is slow and eye-bud germination is deficient. Alternative planting methods have to be adopted in order to improve sugarcane field productivity. This work score the field performance of a tractor mounted planter prototype when transplanting two months old nursery growth sugarcane (Saccharum spp) sprouts, in relation to parameters; sound sprouts treatments, row separation between seedlings, up right placement into the soil, appropriate soil covering and field uniformity at planting. This mechanical equipment was trialed when operating on a readily soil tilled for sugarcane planting, although slightly stoned on the surface. Tractor and implement combination was set to travel at a field speed of 0.3 m s-1 when laying seedlings into the row at 900 mm separation. Transplanting separation between seedlings onto the row had a variation of 3.4%. When assisted by two laborers for planting, the tractor and implement combination can achieve a field capacity of 2.5 ha day-1. Thus, for a field capacity of 2 ha day-1 and operating a 120 workdays per planting season, investment on the machine can be claimed in two years’ time. Consequently, planting of sugarcane sprouts by using the planter prototype is up to eight times more economical when compared to manual transplanting.

Growth and yield stability of tomato (<i>Solanum lycopersicum L.</i>) genotypes in late and early planting seasons in a high rainfall and humid rainforest zone

Growth and yield stability of tomato (<i>Solanum lycopersicum L.</i>) genotypes in late and early planting seasons in a high rainfall and humid rainforest zone

Effects of Polyethylene Microplastics on the Growth and Quality of Brassica campestris L. in a Three-season Consecutive Cultivation

In order to investigate the effects of polystyrene （PS） microplastics with different particle sizes on the growth, development, and quality of Brassica campestris L. （Chinese cabbage） in consecutive seasons, we studied the effects of PS plastics with different particle sizes （<25, 25-48, 48-150, and 150-850 μm） on the growth and development of B. campestris L. and on the supply of nutrients to the soil in a potting experiment in three consecutive seasons. The results showed that PS microplastics had a significant inhibitory effect on the growth of Chinese cabbage in three consecutive seasons, and the fresh weight, chlorophyll b, and total chlorophyll content of Chinese cabbage were reduced by 9.22%-30.4%, 51.5%-88.9%, and 25.3%-67.1%, respectively. PS microplastics also affected the quality of Chinese cabbage in three seasons and significantly reduced cabbage starch （20.6%-73.2%）, Mn （23.9%-56.3%）, Zn （18.8%-23.2%）, and Cu （18.9%-35.1%） and increased its soluble sugar content （18.9%-220%）. Soil quick-acting phosphorus and quick-acting potassium content under the influence of PS microplastics showed the largest decreases of 26.0% and 55.8%, respectively, but had no significant effect on the effective Cu, Fe, Zn, and Mn contents. Overall, the effect of PS microplastics on the growth and quality of Chinese cabbage increased with the decrease in particle size and decreased with the increase in consecutive planting seasons； however, there was no obvious pattern of change in the effect of PS microplastic particle size on the soil fast-acting nutrient content.

Development of National Emission Factor for Rice Production System in Malaysia: A Step Toward Achieving Sustainable Development Goals

Objective: Currently, methane (CH4) emissions from rice cultivation in Malaysia are calculated using the regional’s methane emission factor (EF) of 1.60 kg CH₄ ha⁻¹ day⁻¹, as Malaysia has not yet developed a national emission factor. The objective of this study is to generate a country-specific EF of CH4 emission from rice cultivation in Malaysian rice fields. The EF generated would then be used in future emission estimates and the country’s greenhouse gas (GHG) inventory reports to the United Nations Framework Convention on Climate Change (UNFCCC). Theoretical Framework: The establishment of a national GHG emission factor for rice cultivation in Malaysia is critical for accurate GHG inventory reporting and effective climate change mitigation. This study utilizes the Intergovernmental Panel on Climate Change (IPCC) guidelines to derive a country-specific emission factor, enhancing Malaysia’s compliance with international climate obligations and promoting sustainable agricultural practices. Method: A new national EF was developed from eleven rice planting seasons in rice granary areas (IADA Pulau Pinang, IADA Barat Laut Selangor, MADA and KADA) and non-granary area (Sik, Kedah). The EF was calculated from methane emissions from the new data sets, published journals and unpublished data from MARDI. For the new data set, methane gas (CH4) was measured using a static chamber method (Minamikawa et al., 2015). Sampling of GHG from the gas chamber is carried out in the field every 2 weeks and gas was analysed by a GC System Agilent 7890A gas chromatography. The daily methane flux and methane emission follow the methods by Habib et al. (2007), Fauzi et al. (2023) and the Guidelines for National Greenhouse Gas Inventories for Cropland (IPCC, 2006a). Results and Discussion: The national EF calculated from CH4 gas emissions over eleven rice planting seasons in Malaysia between 2012-2024 was 1.80 kg CH4 ha-1 day-1, which is higher than the current regional EF used (1.60 kg CH4 ha-1 day-1). However, the value is within the range of the default value of 1.30 kg CH4 ha-1 day-1 by the Intergovernmental Panel on Climate Change (IPCC) 2006 and 2.00 kg CH4 ha-1 day-1 (IPCC, 1996). Research Implications: The use of this new EF resulted in 12.49% increase in the national GHG inventory from the rice cultivation sub-sector as compared to using the current regional EF. This initiative is part of a comprehensive plan to enhance and strengthen GHG inventory reporting for Malaysia's agriculture sector, aiming to meet IPCC requirements and progress to Tier 2 status.

High-throughput phenotypic traits estimation of faba bean based on machine learning and drone-based multimodal data

Faba bean is a global food legume crop, and it is essential to accurately and timely determine its plant height, above-ground biomass (fresh and dry weight) and yield for enhancing cultivation practices and planning the next planting season. Traditional ground sampling is a time-consuming and labor-intensive approach. However, the utilization of an unmanned aerial vehicle (UAV) as a high-throughput technique offers a promising alternative strategy for estimating crop phenotypic traits. In this study, a two-year experiment was conducted from 2020 to 2022, where UAV-based multimodal data were collected using red–green–blue, multispectral and thermal infrared sensors. The variables derived from these three sensors and their combinations were used to estimate the fresh weight, dry weight and yield of faba bean based on extreme gradient boosting (XGBoost), random forest, multiple linear regression and k-nearest neighbor algorithms. The following findings were obtained: (1) The use of the maximum percentile crop surface model resulted in the highest estimation accuracy for faba bean plant height. (2) Fusion data from multiple sensors increased the estimation accuracy of faba bean fresh weight, dry weight and yield, the coefficient of determination (R2) improved by 14.22%, 1.45%, and 18.76%, respectively, compared with the best estimation accuracy of a single sensor. (3) The XGBoost algorithm outperformed the other algorithms in estimating fresh weight, dry weight and yield of faba bean. These results demonstrate that multiple sensors and appropriate algorithms can be used to effectively estimate faba bean phenotypic traits and provide valuable insights for agricultural remote sensing research.

The impact of using bee pollen in poultry systems

The use of antibiotic growth promoters in poultry production has resulted in the development of drug resistance, and destruction of the normal beneficial intestinal flora. Therefore, the task of poultry industry is to find alternative solutions to ensure safe products. The aim of this review article was to understand the potential use of bee pollen in poultry production system regarding its impact on performance, carcass traits, immunity, bacterial community, and blood parameters. Bee products such as pollen have been used in traditional medicine and have recently appeared as possible feed additives. Bee pollen is considered the most important substance in the hive, as a basic feed for bees. It consists of a mixture of proteins, amino acids, fats, carbohydrates, and multiple vitamins, minerals, and enzymes. The chemical composition of bee pollen depends mainly on the plant species, geographic region, and season of collection. Bee pollen has many uses in human medicine and livestock production. It has been used to improve general health, and may also act as an antibacterial, antifungal, antioxidant, anti-radiation, anti-carcinogenic, anti-inflammatory, hepato- and cardio-protective, and antidiabetic. Dietary supplementation of bee pollen could increase performance parameters as a growth promotor, enhancing carcass quality. In addition, bee pollen can enhance the immune response, reduce the pathogenic bacterial count, and enhance important blood parameters.

Disentangling the Complex Effects of Seasonal Drought, Floor Mass, and Roots on Soil Microbial Biomass in a Subtropical Moist Forest

Severe seasonal droughts driven by global climate change significantly alter the cycling of carbon and nutrients in forest ecosystems, while the investigation into the impacts of floor mass and plant roots on soil microbial biomass within the context of recurrent seasonal droughts is still rare. To investigate the environmental determinants governing soil microbial biomass with the escalating severity of seasonal droughts, we conducted a study in a montane subtropical moist evergreen broad-leaved forest in southwestern China from June 2019 to May 2023. The study results revealed that soil microbial biomass, as well as soil moisture, floor mass, and plant roots, showed an apparent single-hump modal within one year. In the comparative analysis of the soil microbial biomass fluctuation amplitudes across control and watered plots, a discernible disparity was observed, indicating significant differences in microbial biomass dynamics between the respective experimental conditions. The pooled data revealed a statistically significant influence of seasonal drought, floor mass, plant roots, and their reciprocal interactions on the soil microbial biomass, highlighting these factors as pivotal determinants of microbial community dynamics. This study elucidates the interactive regulatory mechanisms by which seasonal drought, floor mass, and plant roots collectively modulate soil microbial biomass within tropical and subtropical forests, offering insights into the complex ecological processes governing microbial community dynamics. This interactive regulation might influence the trajectory of plant species and soil microbial communities, facilitating their adaptive development and evolutionary responses.

Technical efficiency of sugarcane farming in East Java, Indonesia: A bootstrap data envelopment analysis

Abstract Sugarcane is an essential commodity in Indonesia. However, climate change negatively affects the sugarcane production efficiency. This study aims to measure the technical efficiency of sugarcane farming using a bootstrap data envelopment analysis (DEA) approach, compare the efficiency of irrigated and rain-fed sugarcane farming, and determine the factors affecting the technical efficiency of sugarcane farming in East Java, Indonesia. Primary data were collected from 451 sugarcane farmers during the 2020–2021 planting season. The results indicate that the “bias-corrected” technical efficiency scores of the single- and double-bootstrap approach (0.624 and 0.561) were lower than that of conventional DEA (0.714). The efficiency score of irrigated sugarcane farms (0.593) was higher than that of rain-fed farms (0.529). Moreover, the farmers’ age, household size, dependency, farming experience, training, subsidies, crop diversification, and access to irrigation impacted sugarcane farming’s technical efficiency. Improvement of 1% in training, irrigation access, and subsidies increased the technical efficiency by 0.034, 0.032, and 0.030, respectively. This strategy is expected to enhance the productivity and technical efficiency and reduce the poverty in rural households in East Java.

Influence of improving selections on potato productivity in original seed nurseries in Karelia conditions

In potato seed production, selections contribute to maintaining varietal typicality, increasing yields and improving the quality of seed material. The purpose of this work is to evaluate the effectiveness of improving selections in the first field generation of potatoes under conditions of variability of meteorological factors during the growing season of plants. In the process of crop reproduction, the yield indicators of the super-super elite of three varieties of the early ripeness group (Latona, Impala, Red Scarlett) are reflected during the selection in the first field generation. Using cluster and step-by-step discriminant analyses, three groups of productivity of vegetative offspring were identified for each of the above varieties: I – maximum, II – average, III – minimum. In the experiment, they were used as experimental options for control – offspring without selection. Against the background of the absence of reliable deviations in the number and weight of tubers in the experimental variants from the corresponding controls, a tendency to increase production was revealed.

Sample Type and Processing Plant Differences in the Proportion of Enterohemorrhagic Escherichia coli O157 and Non-O157 Serogroups in Feces and on Hides of Cull Dairy Cattle at Slaughter.

The study was conducted to determine the proportion and concentration of enterohemorrhagic Escherichia coli (EHEC) O157 and six non-O157 (O26, O45, O103, O111, O121, and O145) serogroups and identify seasonal and processing plant differences in feces and on hides of cull dairy cattle processed in commercial slaughterhouses in the United States. Approximately 60 rectal and 60 hide-on samples from matched carcasses were collected in each of three processing plants, in two periods; summer of 2017 and spring of 2018. Samples before enrichment were spiral plated to quantify EHEC, and postenriched samples underwent culture methods that included immuno-magnetic separation, plating on selective media, and PCR assays for identification and serogroup confirmation of putative isolates. An isolate was considered EHEC O157 positive if it harbored serogroup-specific (rfbE), Shiga toxin (stx1 and/or stx2), and intimin (eae) genes and EHEC non-O157 positive if at least one of the non-O157 serogroup-specific, stx1 and/or stx2, and eae genes was identified. Generalized linear mixed models were fitted to estimate overall proportion of positives for EHEC O157 and non-O157 EHEC serogroups, as well as seasonal and processing plant differences in fecal and hide-on proportion of positives. The fecal EHEC proportion at the sample level was 1.8% (95% CI = 0.0-92.2%) and 4.2% (95% CI = 0.0-100.0%) for EHEC O157 and EHEC non-O157, respectively. Hide sample level proportion of positives was 3.0% (95% CI = 0.0-99.9%) for EHEC O157 and 1.6% (95% CI = 0.0-100.0%) for EHEC non-O157. The proportion of EHEC O157 and non-O157 significantly differed by processing plant and sample type (hide vs. feces), but not by season. The association between proportion of EHEC serogroups in feces with the proportion on hides collected from matched cattle was 7.8% (95% CI = 0.6-53.3%) and 3.8% (95% CI = 0.3-30.8%) for EHEC O157 and non-O157, respectively. Taken together, our findings provide evidence of a low proportion of EHEC serogroups in the feces and on hides of cull dairy cattle and that their proportion varies across processing plants.

Effects of Cover Crops on Weed Suppression in the Inter-Row Spaces of Citrus Orchards

Abstract A multi-year study was carried out at two citrus groves with mature trees in Southwest Florida in the United States to evaluate the effects of cover cropping on the citrus inter-row as a sustainable weed management strategy in the Florida citrus production system. Two cover crop (CC) mixes (legume + nonlegume species and only non-legume species) were compared with a no-CC grower standard management (GSM) that utilized the herbicide paraquat for weed suppression in the citrus tree inter-row spaces. We gathered data on the biomass and density of both cover crops and weeds, during the spring and summer/fall CC planting seasons throughout the study years. Both mixes of CCs effectively reduced weed density in the citrus inter-row by 58 to 99% (P<0.05), depending on the growing season and study locations, compared to GSM. Additionally, there were no significant differences observed between the different CC mixes. Similarly, both CC mixes reduced the weed biomass by 95 to 99% (P<0.05) in the citrus inter-row compared to the GSM. However, weed suppression by CCs varied between growing seasons, mainly due to differences in germination and establishment of the CCs in each season.

Plant traits and seasonality shape coexistence and niche segregation patterns among spider species.

Understanding the mechanisms that enable species coexistence is a central question in ecology, as it helps to comprehend species diversity. One of the most common stabilizing mechanisms of coexistence is niche segregation, which can prevent the competitive exclusion of the fittest competitor. Niche segregation can manifest itself at various temporal and spatial scales, allowing provide essential insights into understanding the stabilizing mechanisms facilitating the coexistence of species. We assessed coexistence patterns among flower-dwelling spiders in two ways, in the first set of analyses, we investigated the factors influencing the quantity of spider individuals and species. The second approach we investigate the spatio-temporal segregation between species, effectively examining the coexistence patterns. We observed that the presence of inflorescences per plant, the number of flowers per inflorescence, and the presence of EFNs play a significant role in increasing spider abundance and richness. We find only a marginal seasonal effect, suggesting that spiders have constant access to resources throughout the year. Our niche overlap analysis demonstrated synchrony in the spatial occupation of niches by different spider species. The coexistence patterns appeared to be unaffected by the number of inflorescences. The greater number of inflorescences will enable a greater availability of niches, and consequently more abundance and richness of species of spiders the plant can sustain. Our results suggest that, to mitigate the adverse consequences of competitive interactions, spiders tend to adopt spatial partitioning as a strategy to facilitate the coexistence of spiders living in reproductive structures on plants in the Brazilian savanna.

Optimization of sowing dates for enhanced rice yield: insights from field experiments in the middle and lower reaches of the Yangtze River, China

An efficacious strategy to adapt to climate change involves optimizing the planting season, a technique that has been extensively utilized to enhance the use of solar radiation and temperature resources in rice cultivation. Field experiments were executed in the middle and lower reaches of the Yangtze River, China, employing three distinct rice cultivars and seven disparate sowing periods spanning 2019 to 2021. The objective of assessing the impact of sowing date on apparent radiation use efficiency (RUEA), accumulated temperature use efficiencies (TUE), and overall rice yield. Subsequent to the delay of sowing dates, the duration of the comprehensive growth period initially exhibited a declining trajectory before subsequently escalating, with the reduction predominantly ascribed to a decrease in the number of days preceding heading. Furthermore, there was a tendency for both the mean daily and effective cumulative solar radiation to decline over the course of the growing period. The yield of the three rice varieties demonstrated an initial surge, which was then followed by a subsequent decline in reaction to the delay of sowing dates. A correlation analysis disclosed that solar radiation and effective cumulative temperature (EAT) were the predominant elements impacting grain yield. The outcomes of the path analysis indicate that EAT exerts the most substantial influence on yield, succeeded by cumulative total solar radiation (TSR), while photothermal quotient (PTQ) demonstrates the least impact on yield. There was a significant positive correlation between EAT and cumulative TSR with spikelets per panicle (0.237** and 0.218**), grain filling (0.753** and 0.576**), and grain weight (0.339** and 0.359**), respectively. The findings of this study indicate that an increase in yield is facilitated when the EAT after heading exceeds 594.9 ℃, the EAT surpasses 2016.7 ℃, the cumulative TSR before heading is above 1548.7 MJ m− 2, the cumulative TSR after heading is over 603.0 MJ m− 2, and the cumulative total radiation throughout the entire growth period is more than 2151.8 MJ m− 2. Furthermore, the most optimal sowing date, as identified by this study, is June 6. This study provides key insights into boosting rice productivity in the middle and lower reaches of the Yangtze River, China by analyzing the impact of temperature and solar radiation on yield and identifying optimal growth conditions.Clinical trial number Not applicable.