Agriculture

Nutrient management is a key component of best agronomic practices for optimal crop production. The continuous use of high yielding genotypes and exhaustive cropping systems has resulted in potassium deficiency. Furthermore, the imbalanced use of nutrients, particularly potassium (K), has resulted in persistent depletion from agricultural soils. To address this issue, a field experiment was conducted to determine the influence of different potassium levels under a split application on yield and yield attributes of wheat crops. The experiment was laid out in a randomized complete block design replicated four times. Five K levels (0, 60, 80, 100 and 120 kg ha−1) and different K application timings (whole dose (Basal) at sowing, equal doses at sowing+ 30 DAS, half dose at sowing+ equal doses at 30 +60 DAS and equal doses at sowing+30+60+ 90 DAS). The findings of the study revealed that potassium levels and their application times substantially influenced yield and yield components of w...

The current farming system is heavily reliant on chemical fertilizers, which negatively affect soil health, the environment, and crop productivity. Improving crop production on a sustainable basis is a challenging issue in the present agricultural system. To address this issue, we assumed that the combined use of organic manure and inorganic nitrogen (N) fertilizers can improve rice grain yield and soil properties without the expense of the environment. This study explores the combined effects of cattle manure (CM), poultry manure (PM), and chemical fertilizer (CF) on soil properties, rice growth, physiology, and grain yield and quality. Six treatments in the following combinations were included: T1—no N fertilizer; T2—100% CF; T3—60% CM + 40% CF; T4—30% CM + 70% CF; T5—60% PM + 40% CF; and T6—30% PM + 70% CF. Results showed that across the seasons, treatment T6 increased the net photosynthesis rate, total biomass, grain yield, and amylose content by 23%, 90%, 95%, and 10%, respecti...

Grain filling can directly influence rice yield. However, there is limited information on the growth relationship among grains at different positions on the entire panicle during grain filling. In this study, field experiments were conducted in 2014–2015 to compare the growth dynamics of grains at various positions for two rice cultivars (Nongle 1 and Guifeng 2). The results showed that a high similarity and a slow–fast–slow trend of dry-matter accumulation occurred in all primary branches. However, the maximum grain growth rates of the top primary branches were 86% and 44% higher than basal primary branches of Nongle 1 and Guifeng 2, respectively. Similarly, the maximum final grain weights were 32% and 18% greater in the top primary branches than in the basal primary branches of Nongle 1 and Guifeng 2, respectively. In contrast, the active grain filling duration was 1.5 and 1.3 times longer in the basal primary branches than the top primary branches of Nongle 1 and Guifeng 2, respe...

Continuous cropping of rice (Oryza sativa L.) and wheat (Triticum aestivum L.) deplete soil fertility and reduce crop productivity as well as zinc (Zn) concentrations in rice grains and straw. Low Zn concentrations in rice grains have a negative impact on human health, while low Zn concertation in rice straw creates a nutritional problem for animals. The current high yielding rice varieties and hybrids remove large quantities of Zn from the soils, lowering the residual concentrations of soil Zn for the subsequent crop (e.g., wheat). Field experiments were conducted on farmers field in Malakand with the objective to evaluate the impact of various combinations of phosphorus (0, 40, 80, and 120 kg ha−1) and Zn levels (0, 5, 10, and 15 kg ha−1) on biofortification of Zn in grains and straw of rice genotypes [fine (Bamati-385) vs. coarse (Fakhre-e-Malakand and Pukhraj)]. The results revealed that Zn biofortification in rice genotypes increased with the integrated use of both nutrients (P...

Readily available chemical fertilizers have resulted in a decline in the use of organic manure (e.g., green manures), a traditionally sustainable source of nutrients. Based on this, we applied urea at the rate of 270 kg ha −1 with and without green manure in order to assess nitrogen (N) productivity in a double rice cropping system in 2017.

Conservation farming practices, such as no-tillage and crop residue retention, have been proposed as sustainable management practices. However, it remains unclear how different tillage practices and rice straw retention affect the soil bacterial community (SBC) and the soil C/N ratio in the long term. The objective of this study was to evaluate changes in SBC composition and abundance and soil properties (e.g., carbon (C), nitrogen (N)) and determine their relationship to the soil C/N ratio under long-term no-tillage and straw retention techniques. This study investigates the effect of a long-term field experiment begun in 2008 and continued until 2019 to measure the response of the SBC and soil properties and their relation to different tillage practices, including no-tillage (NT), no-tillage and straw mulching (NT-SM), conventional tillage (CT), conventional tillage and straw mulching (CT-SM), and conventional tillage and straw retention (CT-SR). Soil samples were collected at dep...

Integrons are hot spots for acquiring gene cassettes from the environment and play a major role in the bacterial evolution and dissemination of antimicrobial resistance (AMR), thus posing a serious threat. There are currently studies on integrons and antibiotic resistance genes; however, the presence and association of integrons in different agricultural crops and their subsequent dissemination and role in AMR have not been reported previously. This study examines the abundance of integrons, their gene cassette diversity in various crop soils, and their role in the dissemination of AMR in the southern region of China. Samples from different agri-crop soil, such as rice (R.S), sugarcane (S.S), citrus (C.S), banana (B.S), agricultural runoff (the point where the runoff of all sites meet (R.O)), and wild (non-agricultural) soil (W.S), were collected. Quantitative PCR was used to determine the abundance of integrons, and clone libraries were constructed to examine the gene cassette arra...

The combined use of organic manure and chemical fertilizer (CF) is considered to be a good method for sustaining high crop yields and improving soil quality. We performed a field experiment in 2019 at the research station of Guanxi University, to investigate the effects of cattle manure (CM) and poultry manure (PM) combined with CF on soil physical and biochemical properties, rice dry matter (DM) and nitrogen (N) accumulation and grain yield. We also evaluated differences in pre-and post-anthesis DM and N accumulation and their contributions to grain yield. The experiment consisted of six treatments: no N fertilizer (T1), 100% CF (T2), 60% CM + 40% CF (T3), 30% CM + 70% CF (T4), 60% PM + 40% CF (T5), and 30% PM + 70% CF (T6). All CF and organic manure treatments provided a total N of 150 kg ha−1. Results showed that the treatment T6 increased leaf net photosynthetic rate (Pn) by 11% and 13%, chlorophyll content by 13% and 15%, total biomass by 9% and 11% and grain yield by 11% and 1...

Background Melatonin is considered a potential plant growth regulator to enhance the growth of plants and increase tolerance to various abiotic stresses. Nevertheless, melatonin’s role in mediating stress response in different plant species and growth cycles still needs to be explored. This study was conducted to understand the impact of different melatonin concentrations (0, 50, 100, and 150 μM) applied as a soil drench to maize seedling under drought stress conditions. A decreased irrigation approach based on watering was exposed to maize seedling after drought stress was applied at 40–45% of field capacity. Results The results showed that drought stress negatively affected the growth behavior of maize seedlings, such as reduced biomass accumulation, decreased photosynthetic pigments, and enhanced the malondialdehyde and reactive oxygen species (ROS). However, melatonin application enhanced plant growth; alleviated ROS-induced oxidative damages by increasing the photosynthetic pig...

The excessive use of synthetic nitrogen (N) fertilizers in rice (Oryza sativaL.) has resulted in high N loss, soil degradation, and environmental pollution in a changing climate. Soil biochar amendment is proposed as a climate change mitigation tool that supports carbon sequestration and reduces N losses and greenhouse gas (GHG) emissions from the soil. The current study evaluated the impact of four different rates of biochar (B) (C/B0-0 t ha−1, B1-20 t ha−1, B2-40 t ha−1, and B3-60 t ha−1) and two N levels (N1; low (270 kg N ha−1) and N2; high (360 kg N ha−1)), on rice (cultivar Zhenguiai) grown in pots. Significant increases in the average soil microbial biomass N (SMBN) (88%) and carbon (87%) were recorded at the highest rate of 60-ton ha−1B and 360 kg N ha−1compared to the control (N1C) during both seasons (S1 and S2). The photochemical efficiency (Fv/Fm), quantum yield of the photosystem (PS) II (ΦPS II), electron transport rate (ETR), and photochemical quenching (qP) were enha...

The over-reliance on synthetic nitrogen (N) in current farming is a major concern because of its adverse effects on soil quality, the environment, and crop production. Organic fertilizers such as seaweed extract (SE) and microbial inoculants (MI) provide alternatives to chemical fertilizers that could decrease the amount of synthetic N needing to be applied and improve crop growth productivity. This study evaluated the combined effect of SE and MI with reduced N rates on the growth, biomass accumulation, yield, and yield components of an N-efficient rice cultivar (Baixiang 139-A) and N-inefficient rice cultivar (Guiyu 9-B). Field experiments were conducted in the early and late growing seasons at different sites in Guangxi province, China, in 2019. A total of five treatments, such as T1: N 180 + SE 0 + MI 0 (kg ha–1) (control); T2: N 180 + SE 3 + MI 3 (kg ha –1); T3: N 144 + SE 3 + MI 3 (kg ha–1); T4: N 126 + SE 3 + MI 3 (kg ha–1); and T5: N 108 + SE 3 + MI 3 (kg ha–1) were used. Th...

A field experiment was conducted in 2016 to find out the sequential use of different herbicides with adjuvants (a substance which enhances pesticides efficiency) towards improved rice production and weed management in direct-seeded rice crop. The early postemergence herbicides (Kelion 50 WG, Ryzelan 240 SC, and Nominee 100 SC were applied at full or 75% of the full dose with and without adjuvants i.e. 2% solution of ammonium sulfate (AS) and alkyl ether sulfate (AES) at 14 days after sowing (DAS), followed by late postemergence herbicides i.e. Puma super (7.5 EW) and Sunstar 60 WG at 28 DAS. Application of herbicides with and without adjuvant substantially suppressed weed with weed dry weight at 40 and 60 DAS and improved rice yield attributes over a weedy check. It was found that a combination of 75% of Nominee 100 SC along with adjuvant i.e. AS (2% v/v) resulted in higher biological yield (9.16 t/ha), harvest index (30.65%), more grains per panicle (98.13), 1000 grain weight (21.32 g) with improved seed yield (3.86 t/ha). Also, abortive kernel (5.33), chalky kernels (5.66), opaque kernels (5.00), normal kernel (70.66), water absorptive ratio (4.28), and kernel length (10.13).

The current farming system in China is heavily reliant on synthetic fertilizers, which adversely affect soil quality and crop production. Therefore, the aim of this study was to assess the effect of different nitrogen (N) and phosphorous (P) fertilizer application rate on the growth, yield, and yield components of rice cultivars in the Binyang, Beiliu and Liucheng sites of southern China in the early (March to July) and late season (August to December). The study consisted of three fertilization regimes—CK (N0P0); N180P90 (180 kg N + 90 kg P2O5 ha−1) and N90P45 (90 kg N ha−1 + 45 kg P2O5)—conducted at each of three different experimental sites with four cultivars (Baixang 139, Y Liangyou 1, Guiyu 9, and Teyou 582). Results showed that the leaf area index (LAI) was 38.8% found higher in Guiyu 9 compared with Baxiang at reduced fertilization (N90P45). N90P45 resulted higher dry matter production at the heading (9411.2 kg ha−1) and maturity (15319.5 kg ha−1) stages in Teyou 582 at Beil...

Biochar amendment can influence the abundance, activity, and community structure of soil microbes. However, scare information is present about the effect of the combined application of biochar with synthetic nitrogen (N) fertilizer under paddy field condition. We aimed to resolve this research gap in rice field conditions through different biochar in combination with N fertilizers on soil nutrients, soil microbial communities, and rice grain yield. The present study involves eight treatments in the form of biochar (0, 10, 20, and 30 t ha −1) and N (135 and 180 kg ha −1) fertilizer amendments. The soil microbial communities were characterized using high-throughput sequencing of 16S and Internal transcribed spacer (ITS) ribosomal RNA gene amplicons. Experiential findings showed that the treatments had biochar amendments along with N fertilizer significantly advanced soil pH, soil organic carbon (SOC), total nitrogen (TN), soil microbial carbon (SMBC), soil microbial nitrogen (SMBN), and rice grain yield in comparison to sole N application. Furthermore, in comparison with control in the first year (2019), biochar amendment mixed with N fertilizer had more desirable relative abundance of microorganism, phyla Acidobacteria, Actinobacteria,

In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three different regions during spring 2017. The results showed that the quality traits and yields from different regions of the same variety were different, which reached up to a significant level in most varieties. Among the quality traits, the grain chalkiness rate and chalkiness degree were the most sensitive to different climatic factors, and changes were found among them in different regions, while minor variation was found between brown rice rate and white rice rate. The parameters that were severely affected by temperature were gel consistency, gelatinization temperature, brown rice rate and yield during the filling stage. The critically affected factors by heat were brown rice rate, protein content, essential amino acid and amylose content while brown rice rate, chalkiness rate and gelatinization temperature were substantially affected by water factors. Grain yield and quality were closely related to meteorological factors on different stages after heading. Our results revealed that yield and quality of special rice were significantly influenced by meteorological factors during the grain filling stage.

Irrigation and nitrogen (N) fertilization rates are widely used to increase crop growth and yield and promote the sustainable production of the maize crop. However, our understanding of irrigation and N fertilization in the soil microenvironment is still evolving, and further research on soil bacterial communities under maize crop with irrigation and N management in subtropical regions of China is needed. Therefore, we evaluated the responses of two irrigation levels (low and high irrigation water with 60 and 80% field capacity, respectively) and five N fertilization rates [i.e., control (N0), N200 (200 kg N ha−1), N250 (250 kg N ha−1), N300 (300 kg N ha−1), and N350 (350 kg N ha−1)] on soil bacterial communities, richness, and diversity. We found that both irrigation and N fertilization significantly affected bacterial richness, diversity index, and number of sequences. Low irrigation with N300 treatment has significantly higher soil enzymes activities, soil nutrient content, and b...

In Khyber-Pakhtunkhwa, Pakistan, wheat yield is subjected to the availability of water and the proper rate of Nano-black carbon in the soil. Delay in the rain and unsuitable soil health cause severe yield reduction. Therefore this experiment was conducted to compare irrigation levels in relation to a different rate of Nano-black carbon to find out the high yielding fact that could enhance wheat productivity and food security. Three different irrigation levels (250-mm, 275-mm and 300-mm), were compared in early growth stages with five different rates of Nano-black carbon (5Mg ha-1 , 10Mg ha-1 , 15Mg ha-1 , 20Mg ha-1 and 25Mg ha-1). All other agronomic practices were kept similar for each replication. Data was recorded on different growth parameters such as days to emergence, emergence m-2 , plant height, spike length, number of spikes m-2 , thousandgrain weight and grain yield. The study confirmed that almost all irrigation levels were prominent but a significant reduction in different parameters was observed with variation in Nano-black carbon that could ultimately affect soil health and productivity. It was concluded that the proper rate of Nano-black carbon can significantly enhance the development of the roots system which may ultimately increase the shoot growth and final yield. Wheat irrigation levels (250 mm) can properly save water and increase wheat productivity in combination with Nano-black carbon amendments.

In recent years, biochar application to soil has become more popularized due to its potential roles on soil fertility, plant growth, and development. In this review, we discussed the impact of biochar on the relative abundance of soil proteobacteria and its relationship with soil physiochemical properties under different rhizospheres. It was observed that biochar applied to different soil improved proteobacteria, and its lowest and highest relative abundance was ranged from 30-80%, respectively. A positive relationship of soil proteobacteria with soil pH, total nitrogen, available phosphorous, available potassium, total carbon were observed in several studies. Both the relative abundance of proteobacteria and its relationship with soil properties depend on biochar type, soil type, and fertilizers applied to the soil. Most of the ammonia-oxidizing bacteria including nitrogen-fixing bacteria, ammonia-oxidizing bacteria, cellulosedecomposing bacteria, nitrifying bacteria, and denitrifying bacteria belong to proteobacteria, which plays a significant role in nitrogen recycling that is beneficial for the plant growth, yield and fruits/seeds quality. Furthermore, a positive relationship between soil proteobacteria and plant yield was also highlighted. In this context, the use of biochar plays a potential role to improve the relative abundance of proteobacteria in sustainable agriculture. We highlighted future research guidelines that might benefit the sustainable agricultural system. Moreover, further studies are needed to explore the potential role of biochar application on Proteobaceria families such as Alphaproteobacteria,