Estimating Nutrient Uptake Requirements for Melon Based on the QUEFTS Model

Imbalanced and excessive fertilizer application has resulted in low yields and reduced nutrient use efficiency for melon production in China. Estimating nutrient requirements is crucial for effectively developing site-specific fertilizer recommendations for increasing yield and profit while reducing negative environmental impacts. Relationships between the yield and nutrient uptake requirements of above-ground dry matter were assessed using 1127 on-farm observations (2000–2020) from melon production regions of China. The quantitative evaluation of fertility of tropical soils (QUEFTS) model was used to estimate nutrient requirements. It predicted a linear increase in yield at balanced nutrient uptake levels until the yield reached approximately 60–80% of the potential yield. In order to produce 1000 kg of fruit, 2.9, 0.4 and 3.2 kg/ha of N, P and K (7.2:1.0:7.8), respectively, were required for above-ground parts, while the corresponding nutrient internal efficiencies were 345.3, 2612.6 and 310.0 kg per kg N, P and K, respectively, whereas 1.4, 0.2 and 1.9 kg of N, P and K were required to replace nutrients removed after harvest. The corresponding fruit absorption rates were 47.0%, 59.5% and 58.2%, respectively. Field validation experiments confirmed the consistency between observed and simulated uptake rates, indicating that this model could estimate nutrient requirements. These findings will help develop fertilizer recommendations for improving melon yield and nutrient use efficiency.

Identification and Characterization of a Garlic Virus E Genome in Garlic (Allium sativum L.) Using High-Throughput Sequencing from India

Garlic (Allium sativum L.) plants exhibiting mosaics, deformation, and yellow stripes symptoms were identified in Meerut City, Uttar Pradesh, India. To investigate the viruses in the garlic samples, the method of high-throughput sequencing (HTS) was used. Complete genome of the garlic virus E (GarV-E) isolate (NCBI accession No. MW925710) was retrieved. The virus complete genome comprises 8450 nucleotides (nts), excluding the poly (A) tail at the 3′ terminus, with 5′ and 3′ untranslated regions (UTRs) of 99 and 384 nts, respectively, and ORFs encoding replicase with a conserved motif for RNA-dependent RNA polymerase (RdRP), TGB1, TGB2, TGB3, serine-rich protein, coat protein, and nucleic acid binding protein (NABP). The sequence homology shared 83.49–90.40% and 87.48–92.87% with those of GarV-E isolates available in NCBI at the nucleotide and amino acid levels, respectively. Phylogenetic analysis showed a close relationship of this isolate from India (MW925710) with GarV-E isolate YH (AJ292230) from Zhejiang, China. The presence of GarV-E was also confirmed by RT-PCR. The present study is the first report of GarV-E in garlic cultivar Yamuna Safed-3 grown in northern India. However, further studies are needed to confirm its role in symptom development, nationwide distribution, genetic diversity, and potential yield loss to the garlic in India.

Prediction of potential and attainable yield of wheat : A case study on yield gap

This study reports the role of field experimentation and system simulation in better quantifying the productivity of wheat crop, and examine how knowledge on potential productivity can improve the efficiency of the production system. When knowledge from field experimentation is utilised into crop weather simulation models, gap between actual, attainable and potential yield for a given environment can be determined and opportunities for yield improvement can be assessed. Results show that while actual district average yields show increasing trend, decreasing trend is noticed in potential and attainable yield. While the total and management yield gap is decreasing over time, research yield gap does not show any trend, it is nearly stagnant from early eighties to late nineties. The study reported here presents the advantage of simulation models to determine the yield gap against a variable annual yield potential for a agro-climatic region.

Genetic Yield Gains and Changes in Morphophysiological-Related Traits of Winter Wheat in Southern Chilean High-Yielding Environments

Both the temperate-humid zone and the southern part of the Mediterranean climate region of Chile are characterized by high wheat productivity. Study objectives were to analyze the yield potential, yield progress, and genetic progress of the winter bread wheat (Triticum aestivum L.) cultivars and changes in agronomic and morphophysiological traits during the past 60 years. Thus, two field experiments: (a) yield potential and (b) yield genetic progress trials were conducted in high-yielding environments of central-southern Chile during the 2018/2019 and 2019/2020 seasons. In addition, yield progress was analyzed using yield historical data of a high-yielding environment from 1957 to 2017. Potential yield trials showed that, at the most favorable sites, grain yield reached ∼20.46 Mg ha–1. The prolonged growing and grain filling period, mild temperatures in December-January, ample water availability, and favorable soil conditions explain this high-potential yield. Yield progress analysis indicated that average grain yield increased from 2.70 Mg ha–1 in 1959 to 12.90 Mg ha–1 in 2017, with a 128.8 kg ha–1 per-year increase due to favorable soil and climatic conditions. For genetic progress trials, genetic gain in grain yield from 1965 to 2019 was 70.20 kg ha–1 (0.49%) per year, representing around 55% of the yield progress. Results revealed that the genetic gains in grain yield were related to increases in biomass partitioning toward reproductive organs, without significant increases in Shoot DW production. In addition, reducing trends in the NDVI, the fraction of intercepted PAR, the intercepted PAR (form emergence to heading), and the RGB-derived vegetation indices with the year of cultivar release were detected. These decreases could be due to the erectophile leaf habit, which enhanced photosynthetic activity, and thus grain yield increased. Also, senescence of bottom canopy leaves (starting from booting) could be involved by decreasing the ability of spectral and RGB-derived vegetation indices to capture the characteristics of green biomass after the booting stage. Contrary, a positive correlation was detected for intercepted PAR from heading to maturity, which could be due to a stay-green mechanism, supported by the trend of positive correlations of Chlorophyll content with the year of cultivar release.

Analysis the agronomic character and inheritance of fragrant genes in F2 progenies of Sigupai and Yinzhan

Sigupai is one of Aceh’s local rice that highly popular because of the distinctive scent. Sigupai is still widely grown by the farmers in the southern western region of Aceh. However, this local rice has inferior production, height plant architecture, deep age and the average of production about 4 tons ha-1. The improvement of Sigupai local rice from the agronomic character and the harvest age can be done through crosses with Yinzhan varieties that carry sd-1 genes. The study aims to analyze changes in agronomic character and fragrant gene inheritance in Sigupai/Yinzhan F2 derived. Analysis of agronomic character is carried out by observing harvest age, plant height, weight of 1000 grains, grain weight per clump and yield potential per hectare. The planting material used was F2 derivative of Sigupai/Yinzhan as many as 104 individuals planted in pots. PCR analysis was conducted to analyze the presence of fragrant genes in F2 progenies of Sg/Yz. The data was analyzed with Chi-Square analysis. The results showed 104 plant genotypes analyzed by PCR, 64.42% of F2 progenies Sigupai/Yinzhan inherited the fragrant gene. The results of analysis of agronomic character showed 62 genotypes there were 95.08% of ripening aged, 59.01% had a short stem architecture and 6 genotypes (9.83%) had a potential yield of 4,04,-5,33 tons ha-1.

Is Organic Rice bean (Vigna umbellata) Farmers Economically better Off? AnEmpirical Analysis

The study was conducted in North Eastern Hill (NEH) region of India during 2018-2020.Multistage sampling technique was adopted. Sikkim was selected purposively as the controlstate and Nagaland was selected based on the highest area and production under pulses. 60respondents each from organic adopter and non-adopter were selected making a total samplesize of 120. The growth rate in area, production and productivity at the world, India andNEH states were found to be positive. However, higher growth rate were observed forthe NEH region. Significance difference was observed only on cost of fertilizers. The totalcost of rice bean cultivation was lower in organic adopter by 1.71 per cent. The averageyield was significantly higher for the organic adopter. The gross income and net incomewere also higher for the organic adopter. Organic farming was found to be more profitableand it can enhance the farmer’s income. Allocative efficiency indicates that all the resourcesused in the region need to be increase so as to achieve the maximum potential yield andhenceforth increase the returns.

Climate and Sustainable Food Security

Agriculture is the world's largest solar energy harvesting enterprise. In the Indian context, the last few decades have witnessed unprecedented growth in agricultural production largely due to productivity improvement. However, the gap between potential yield and farmers fields is still high. This paper highlights the various socioeconomic issues that dominate the variability in agricultural production at the field level. Monsoon management of agriculture and human livelihoods has been a traditional experience in India. However, in the current context of wide spread concerns about global climatic change there is a need to translate climatic information into practical tools for the development and sustainment of agriculture. This paper makes a case for the development of a suitable strategy for climate management, in the context of the unique socio-economic structure of the country.

Statistical Modelling for the Source Rock Parameters of the Montney Formation, NE British Columbia, Canada

Hydrocarbons in self-sourced reservoirs are determined by the concentration and maturation of organic matter in sediments. As a result, lowering risk in unconventional resource research and development requires knowledge of hydrocarbon potentiality factors. The geochemical data for the Montney Formation samples studied suggest that it is a fair to good source rock with type IV kerogen that can generate gas in general. The statistical modelling of the analyzed data reveals a valuable technique for identifying characteristics, clusters, and linkages that affect source rock assessment. The Spearman’s correlation coefficient showed a good positive correlation between the total organic carbon (TOC) and free hydrocarbons (S1), generating potential (S2), and potential yield (GP). There was a weak correlation with the maturity index (Tmax) and hydrogen index (HI) and a highly negative correlation between the TOC and oxygen index (OI). On the other hand, the principal component analysis (PCA) showed the presence of three factors affecting the source rock evaluation. Factor 1 included TOC, S1, and S2, which are related to organic richness and hydrocarbon potentiality; factor 2 contained the production index (PI), and the generated CO2 (S3) was related to the organic matter source. Factor 3 included the Tmax and HI related to the type of organic matter and thermal maturity. In addition, the TwoStep cluster analysis separated the source rock in the study area into two major groups. Cluster 1 is characterized relatively by high HI, TOC, S1, S2, and PI, with Tmax < 455 °C indicating good source rock in the mature level with the capability to generate little oil and condensate gas. Cluster 2 is characterized by relatively low HI, TOC, S1, S2, and PI, with Tmax > 455 °C, indicating an over-mature source rock in the dry gas window.