Root Yield Research Articles

Analysis of the Effects of Organic and Synthetic Mulching Films on the Weed, Root Yield, Essential Oil Yield, and Chemical Composition of Angelica archangelica L.

Angelica archangelica L. (Garden angelica) is a medicinal and aromatic plant from the Apiaceae family, originating from North Europe (Iceland, Greenland, and Scandinavian countries). A. archangelica is commonly used in traditional medicine to treat anxiety, insomnia, stomach and intestinal disorders, skin conditions, respiratory problems, and arthritis. This plant is generally cultivated for its root and seed where the essential oil (EO) is concentrated the most. Angelica archangelica cultivation has a lot of challenges but the main one is weed control; so, the aim of this study was to investigate the influence of four different mulch types as non-chemical weed control measures on weediness, fresh root yield, and EO chemical composition and yield from A. archangelica roots. A field trial was conducted with the following six treatments: two organic mulches, two synthetic mulches, and two controls (regular hand-weeded and weeded). The results show that the most present weeds were Ambrosia artemisiifolia, Chenopodium album, Polygonum aviculare, and Polygonum lapathyfolium, but synthetic mulch foils achieved the best weed suppression (100%). These fields also achieved the highest fresh root yield in both of the experimental seasons. The highest EO yield was detected with agrotextile mulch foil at season I (0.41%, v/w) and with the weeded control (0.51%, v/w) at season II, but dominant components at both seasons were α-pinene and β-phellandrene. The results suggest that the agrotextile black and silver–brown mulch foils achieved complete weed suppression, but the agrotextile black mulch foil had a better effect on fresh root yield, EO yield, and its chemical composition.

Effects of Bio and water-soluble fertilizers on sweet potato yield, quality and soil properties in a continuous cropping system under plastic film-mulched drip-fertigated field conditions.

To verify an effective approach for alleviating problems associated with the consecutive monoculture of sweet potato, five fertilizer treatments were designed under plastic film-mulched, drip-fertigated conditions in fields continuously planted with sweet potato over five years. These treatments included: (1) no fertilizer application, (2) basic application of water-soluble (WS) fertilizer, (3) basic application of biofertilizer (BF) and WS fertilizer, (4) split application of WS fertilizer, and (5) combined basic application of BF and split application of WS fertilizer. The effects of BF and WS fertilizer applications on yield, quality, and soil properties were evaluated. Fertilizer applications had positive effects on increasing soil activities and nutrients compared with no fertilizer application. Split fertigation with WS fertilizer increased the activities of soil dehydrogenase (DHA) by 10.94 ~ 14.74%, alkaline phosphatase (ALP) by 4.97 ~ 5.13%, and soil organic matter (SOM) by 10.43 ~ 12.47% in the second year compared with a single application. In both years, split fertigation exerted positive effects on increasing dry matter (DM) accumulation in tuberous roots and increased the productive efficiency in nitrogen (N), phosphorus (P), and potassium (K) fertilizers. BF application for two consecutive years increased the activities of soil sucrase by 7.05 ~ 17.83%, DHA by 18.65 ~ 21.34%, ALP by 6.87 ~ 7.03%, soil available P by 18.34 ~ 28.10%, and SOM by 8.18 ~ 10.17% compared with the no BF application. BF also increased the root yield by 8.88 ~ 14.14%, the carotenoid content in tuberous roots by 20.38 ~ 30.64%, and the K utilization efficiency by 11.09 ~ 14.97%. The combination of BF and split fertigation for two consecutive years was most conducive to the activation of soil nutrients, maintenance of soil fertility, and improvement in yield and quality, which could mitigate problems associated with the consecutive monoculture of sweet potato.

Evaluation of yield and stability of sugar beet (beta vulgaris L.) genotypes using GGE biplot and AMMI analysis

Rhizomania is the most destructive sugar beet disease in the world, and in recent years, it has widespread in most of the sugar beet growing areas in Iran. Since the control of this soil-borne disease is a difficult task, the use of resistant genotypes is known as the best measure against the disease. The ultimate goal of sugar beet breeders is to produce genotypes that can be used in both infected and non-infected fields without any reduction in terms of yield and quality. Twenty-one sugar beet genotypes along with four controls were evaluated in randomized complete block design with four replications in fields with natural infection to rhizomania in five research stations. Important sugar beet traits including root yield, sugar yield, sugar content, and white sugar yield were evaluated for two years (2021 and 2022). For all traits, location was the main source of variation that spanned 33 to 55% of the total sum of the square followed by the location×year×genotype accounted for 3–40% of the variation. Based on the results of analysis of variance, multivariate stability parameters were computed to evaluate the genotypes’ stability. The first two principal components (IPCA1 and IPCA2) generated by GGE biplot contributed for 31.3 and 17.5% difference in genotype×environment interaction for root yield, respectively. According to the GGE biplot, genotypes RM-11 and RM-12 were identified as the winning genotypes across environments for both root yield and white sugar yield traits whereas AMMI model identified RM-14 and RM-9 (for root yield) and RM-1 (for white sugar yield) as best genotypes. Based on the ideal genotype ranking, RM-11 and RM-10 were the best performer with a high mean yield as well as stability in the studied environments. The biplot rendered using the weighted average of absolute scores (WAASB) and root yield and white sugar yield identified RM-11 and RM-9 as superior genotypes in terms of yield and stability. The selected genotypes can be used in breeding programs to transfer the disease resistance and cultivar development.

UHPLC-MS/MS analysis of the influence of paclobutrazol application on Ophiopogon japonicus

The pharmacological effects of Ophiopogon japonicus are influenced by its active substances like saponins and flavonoids, which are crucial for assessing its quality. An ultra-high performance liquid chromatography tandem triple quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for the qualitative and quantitative assessment of 20 saponins and flavonoids in O. japonicus. The average recovery of these compounds ranged from 70% to 130%, with relative standard deviations (RSD) between 0.11% and 16.46%. Planting O. japonicus in Santai County (Sichuan, China) and investigated the impact of 0.6, 1.3, 2.8, 5.6, and 11.3g/L concentrations of paclobutrazol on both root yield and the levels of saponins and flavonoids in O. japonicus. Lower paclobutrazol concentrations (1.3g/L) led to increased levels of saponins and flavonoids in O. japonicus such as ophiopogonin D′, ruscogenin and ophiopogonanone F, with paclobutrazol residues measuring 77.17μg/kg DW. This preliminary insight into the influence of paclobutrazol and production of saponin flavonoids in O. japonicus bears significance for its larger industrial production.

Multi-trait selection for mean performance and stability in purple-fleshed sweet potato

Few purple-fleshed sweet potato (PFSP) cultivars are available for Brazilian growers, urging for the development of new and adapted cultivars. PFSP breeding programs should include multiple traits during the selection process to increase the chances of developing an adequate genotype, specially yield-related and quality-related traits. The objective was to select promising PFSP genotypes based on yield and tuberous-roots-related traits exploring genotype x environment interaction (GEI). Four experiments were carried out, in which 23 pre-selected PFSP genotypes were evaluated based on yield and quality traits, after screening among 2500 experimental genotypes. The first experiment adopted an augmented block design, with ‘Luiza’ interspersed as a control. From this first experiment, the 19 experimental genotypes with the best performance were selected for the following three experiments, which were conducted in a randomized block experimental design, with three replications each, including ‘Luiza’ as control. The best genotypes were selected in the first experiment using the multi-trait genotype-ideotype distance index (MGIDI). For the following experiments, the performance of the genotypes was assessed using deviance analysis, genotypic stability through weighted average of absolute scores (WAASB) index, and the multi-trait stability index (MTSI). In the first experiment, three factors were retained, being associated to commercial production of tuberous roots (‘K-104′, ‘K-25′ and ‘U1–29′), total production of tuberous roots (‘K-110′, ‘C-42′, ‘F-16′, and ‘U1–29′), and quality of tuberous roots (‘F-22′), respectively. Desired gains were observed for all traits. For the experiments II, III, and IV five factors were retained, being four related to quality of tuberous roots and one to yield components. The GEI was significant for yield-related traits and desired gains were observed for most traits. Due to high commercial tuberous root yield and low WAASB values, the genotypes ‘U1–29′, ‘K-98′, ‘F-22′, ‘K-57′, ‘C-36′, ‘U1–15′, ‘K-25′, and ‘U2–12′ were highly productive and stable. The genotypes selected by the MTSI index were ‘U1–15′, ‘U2–10′, ‘U1–29′, ‘K-98′, and ‘K-78′. The multi-trait selection enabled the identification of promising genotypes highlighting their strengths and weaknesses.

Appropriate Planting Density Can Improve the Storage Root Yield and Commercial Features of Sweet Potato (Ipomoea batatas L.) by Optimizing the Photosynthetic Performance

Appropriate Planting Density Can Improve the Storage Root Yield and Commercial Features of Sweet Potato (Ipomoea batatas L.) by Optimizing the Photosynthetic Performance

PHENOTYPIC DIVERSITY OF SWEET POTATO (IPOMOEA BATATAS[L.]LAM.) GERMPLASMUSING QUANTITATIVE TRAITS: A PRE- BREEDING STUDY IN TOGO

Objective: Sweet potato is a root and tuber crop which contribute to food security in Togo. However, little scientific data exists on the genetic variability of cultivars grown in Togo, although this information is a prerequisite for development of new varieties. The objective of this study was to explore the phenotypic diversity within Togos sweet potato cultivars. Materials and Methods: The germplasm is composed of sixty five (65) cultivars from Togo and sixteen (16) exotic varieties introduced from Burkina Faso breeding unit. The experiment was laid out in a 9 x 9 lattice square design with three replicates. In total, sixteen (16) quantitative traits were evaluated using the sweet potato ontology as described by CIP. Results:Descriptive statistics, ANOVA and PCA revealed high variability for traits such as root yield, dry matter content, aboveground biomass, stem length, internode length and stem diameter. Cluster analysis performed on the basis of the Euclidean distance between cultivars using Ward method as aggregation criterion has revealed four phenotypic clusters. Clusters I and II are composed of varieties with low root yield (12.95 and 15.87 t.ha-1) and high dry matter content (29.68 and 26.86%). Clusters III and IV are made of varieties exhibiting high aboveground biomass (37.74 and 50.75 t.ha-1), high fresh root yield (16.06 and 20.18 t.ha-1) and low dry matter content (24.62 and 23.84%). The variability observed in this gene bank constitutes a basis for genetic improvement programmes of sweet potato in Togo.

Comparison of Root Development, Photosynthetic Characteristics, Growth, and Yield of Seedling and Grafted Tomatoes in the Long-Term Cultivation of Venlo Greenhouse

Comparison of Root Development, Photosynthetic Characteristics, Growth, and Yield of Seedling and Grafted Tomatoes in the Long-Term Cultivation of Venlo Greenhouse

Evaluation of the performance and stability of early maturing orange-fleshed sweetpotato genotypes in selected areas in Ethiopia.

Orange-fleshed sweetpotato varieties that mature and harvest sooner play an important role in addressing food and nutrition demands in areas where irregular rainfall makes sustainable production challenging. A national variety trial was conducted in 2021 and 2022 during the main cropping season using ten OFSP genotypes in three locations in Sidama, South, and Oromia regions of Ethiopia, namely Hawassa, Arbaminch, and Koka, respectively. The objective of this study was to develop and select early-maturing and high-yielding OFSP genotypes for short-term harvesting (3-4 months). The field trial was conducted in a randomized complete block design with three replications. Data were collected on root yield and yield-related traits, sweetpotato virus disease reactions (SPVD), root dry matter (DMC), and beta-carotene contents (BCC) and were subjected to analysis of variance. A genotype plus genotype by environment interaction (GGE) bi-plot was also used to determine genotype stability. The results showed the presence of highly significant (p<0.001) differences among locations and genotypes, reflecting the existence of differential responses among genotypes in varied locations. Based on combined analysis, G3 (13NC9350A-9-3) outperformed the other genotypes for most of the traits considered, except for DMC, i.e., which has an equivalent to the check variety (Alamura) and showed a yield advantage of 41.4% over it. The GGE biplot also revealed that the G3 was the vertex genotype with the consistent performance in all environments. It had a low score of 1.39 on the 1-9 scoring scale, indicating that it falls within the resistant range, with adequate levels of BCC (5.5 mg/100 g) and DMC (30.0%). Furthermore, G3 is an early-maturing variety, which allows other crops to be grown in double and relay cropping systems. Therefore, based on its outstanding performance, G3 is recommended for verification and release for cultivation in mid- to low-land areas in Ethiopia.

2023: a soil odyssey–HeAted soiL-Monoliths (HAL-Ms) to examine the effect of heat emission from HVDC underground cables on plant growth

BackgroundThe use of renewable energy for sustainable and climate-neutral electricity production is increasing worldwide. High-voltage direct-current (HVDC) transmission via underground cables helps connect large production sides with consumer regions. In Germany, almost 5,000 km of new power line projects is planned, with an initial start date of 2038 or earlier. During transmission, heat is emitted to the surrounding soil, but the effects of the emitted heat on root growth and yield of the overlying crop plants remain uncertain and must be investigated.ResultsFor this purpose, we designed and constructed a low-cost large HeAted soiL-Monolith (HAL-M) model for simulating heat flow within soil with a natural composition and density. We could observe root growth, soil temperature and soil water content over an extended period. We performed a field trial-type experiment involving three-part crop rotation in a greenhouse. We showed that under the simulated conditions, heat emission could reduce the yield and root growth depending on the crop type and soil.ConclusionsThis experimental design could serve as a low-cost, fast and reliable standard for investigating thermal issues related to various soil compositions and types, precipitation regimes and crop plants affected by similar projects. Beyond our research question, the HAL-M technique could serve as a link between pot and field trials with the advantages of both approaches. This method could enrich many research areas with the aim of controlling natural soil and plant conditions.

Effects of Different Straw Returning Periods and Nitrogen Fertilizer Combinations on Rice Roots and Yield in Saline–Sodic Soil

Straw return is an effective management practice for improving physical and chemical properties of saline–sodic soil in Northeast China. Straw decomposition and nutrient release are deeply influenced by soil and climatic factors. In Northeast China, straw decomposes slowly due to the long winter with low temperatures. Therefore, the season of straw return may be a key issue affecting rice. However, the impact of returning straw in different seasons on rice is disregarded and not commonly researched. We conducted a 2-year field experiment, including two residue management treatments: spring straw return treatment (SR) and autumn straw return treatment (AR), each containing five different N rates (0, 90, 180, 270, and 360 kg ha−1) as sub-treatments. The results reveal that, compared with the spring straw returning treatment, the autumn straw returning treatment significantly improved root morphology and root vigor and increased the number of spikes per unit area, which directly increased rice yield by 4.76% (2020) and 6.62% (2021). In addition, rice yield showed an increasing and then decreasing trend with the increase in N fertilizer application, and it was at its maximum when the N application rate was 270 kg ha−1. Compared to the spring straw return treatment, the autumn straw return treatment was able to reduce 31.46% (2020) and 38.48% (2021) of N fertilizer application without decreasing rice yield. Our findings demonstrate that straw return combined with nitrogen fertilization may be a promising management practice for improving rice root systems and yield in saline–sodic soils, and under the conditions of the autumn straw returning treatment, the best nitrogen fertilizer application rate was 270 kg ha−1.

Partial substitution of phosphorus fertilizer with iron-modified biochar improves root morphology and yield of peanut under film mulching.

Peanut production is being increasingly threatened by water stress with the context of global climate change. Film mulching have been reported to alleviate the adverse impact of drought on peanut. Lower phosphorus use efficiency is another key factor limiting peanut yield. Application of iron-modified and phosphorus-loaded biochar (BIP) has been validated to enhance phosphorus utilization efficiency in crops. However, whether combined effect of film mulching and BIP could increase water use efficiency and enhance peanut production through regulating soil properties and root morphologies needs further investigation. A two-year (2021-2022) pot experiment using a split-plot design was conducted to investigate the effects of phosphorus fertilizer substitution using BIP on soil properties, root morphology, pod yield, and water use of peanut under film mulching. The main plots were two mulching methods, including no mulching (M0) and film mulching (M1). The subplots were four combined applications of phosphorus fertilizer with BIP, including conventional phosphorus fertilizer rates (PCR) without BIP, P1C0; 3/4 PCR with 7.5 t ha-1 BIP, P2C1; 3/4 PCR with 15 t ha-1 BIP, P2C2; 2/3 PCR with 7.5 t ha-1 BIP, P3C1; 2/3 PCR with 15 t ha-1 BIP, P3C2. The results indicated that regardless of biochar amendments, compared with M0, M1 increased soil organic matter and root morphology of peanut at different growth stages in both years. In addition, M1 increased peanut yield and water use efficiency (WUE) by 18.8% and 51.6%, respectively, but decreased water consumption by 25.0%, compared to M0 (two-year average). Irrespective of film mulching, P2C1 increased length, surface area, and volume of peanut root at seedling by 16.7%, 17.7%, and 18.6%, at flowering by 6.6%, 19.9%, and 29.5%, at pod setting by 22.9%, 33.8%, and 37.3%, and at pod filling by 48.3%, 9.5%, and 38.2%, respectively (two-year average), increased soil pH and organic matter content during peanut growing season, and increased soil CEC at harvest. In general, the M1P2C1 treatment obtained the optimal root morphology, soil chemical properties, WUE, and peanut yield, which increased peanut yield by 33.2% compared to M0P1C0. In conclusion, the combination of film mulching with 7.5 t ha-1 BIP (M1P2C1) effectively improved soil chemical properties, enhanced root morphology of peanut, and ultimately increased peanut yield and WUE.

The structure and function of rhizosphere bacterial communities: impact of chemical vs. bio-organic fertilizers on root disease, quality, and yield of Codonopsis pilosula.

Long-term use of chemical fertilizers (CFs) can cause soil compaction and acidification. In recent years, bio-organic fertilizers (BOFs) have begun to replace CFs in some vegetables and cash crops, but the application of CFs or BOFs has resulted in crop quality and disease occurrence. This study aimed to analyze the microbial mechanism of differences between CFs and BOFs in root disease, quality, and yield of tuber Chinese herbal medicine. We studied the effects of CFs, organic fertilizers, commercial BOFs, biocontrol bacteria BOFs, and biocontrol fungi BOFs on rhizosphere microbial community structure and function, root rot, quality, and yield of Codonopsis pilosula at different periods after application and analyzed the correlation. Compared to CFs, the emergence rate and yield in BOF treatments were increased by 21.12 and 33.65%, respectively, and the ash content, water content, and disease index in the BOF treatments were decreased by 17.87, 8.19, and 76.60%, respectively. The structural equation model showed that CFs promoted the quality and yield of C. pilosula by influencing soil environmental factors, while BOFs directly drove soil bacterial community to reduce disease index and improve the quality and yield of C. pilosula. There was a stronger interaction and stability of soil microbial networks after BOF treatments. Microlunatus, Rubrobacter, Luteitalea, Nakamurella, and Pedomicrobium were identified as effector bacteria, which were related to disease prevention and yield and quality increase of C. pilosula. Microbial functional analysis indicated that the signal transduction and amino acid metabolism of soil bacteria might play a major role in improving the quality and yield of C. pilosula in the early and middle growth stages. In conclusion, compared to CFs, BOFs obtained a lower disease index of root rot and a higher quality and yield of C. pilosula by changing the structure and function of the rhizosphere bacterial community.

Deep Rooting as an Indicator of Deep Soil Water and N Uptake in Potato (Solanum tuberosum L.)

AbstractBreeding for potato deep roots can increase water and nitrogen uptake by potatoes and it can be an option to maintain stable yields with decreased inputs. This study investigates the relationship between potato root characteristics, water stress resistance and deep soil nitrogen uptake, accessing variations among cultivars and nitrogen fertilization levels. Thirteen potato cultivars were grown during 2018 and 2020 at a semi-field root phenotyping platform in Denmark. Root growth was monitored via minirhizotron tubes down to 1.8 m soil depth. Drought treatment started in the mid-June and deep soil nitrogen uptake was tracked via 15N isotope application at 1.3–1.4 m soil depth during tuber formation. Water stress resilience was identified using 13C natural discrimination process in plants. Tuber samples were analyzed for 15N and 13C content. While drought affected potato yield (not always significantly), it did not affect nitrogen uptake. Root length and distribution varied among varieties, with deeper roots (down to 1.30 m) observed in August. Statistical differences (p &lt; 0.05) in root length, yield and nitrogen uptake were found among varieties. Cultivars with longer growing season exhibited larger, deeper roots and increased nitrogen uptake from deep soil. High correlation (R = 0.8) between deep roots and 15N uptake was observed for all varieties. Deeper roots are contributing to deep soil nitrogen uptake, but 13C content in tubers is not a reliable indicator of water stress resilience. Despite this, the study suggests the potential for breeding potatoes with deep roots to achieve stable yields, considering differences in water and nitrogen uptake among varieties.

GWAS for root yield and its contributing traits in Withania somnifera (L.) dunal: First report

Ashwagandha [Withania somnifera (L.) Dunal] is a significant medicinal plant, with limited information on its genetic variability. This study evaluateed genetic diversity among 96 ashwagandha genotypes with the aim of developing strategies to improve root yield and secondary metabolites. A joint ANOVA indicated significant variability within the evaluated panel. Key traits, such as root girth, fresh root yield and dry root yield showed positive and significant correlations at both tested years. Molecular markers (SRAP, ISSR, and SSR) were used to assess genetic diversity. Amplified PCR products ranged from 210 bp (SRAP-22) to 1350 bp (SRAP-19), with PIC value ranged from 0.332 (SSR 20) to 0.494 (ISD 11), indicated moderate informativeness of markers. Genetic diversity analysis using Dice's coefficient formed six clusters, identifying two genotypes (86 and 87) as highly diverse. Population structure analysis revealed five clusters with an Fst range of 0.21–0.36, indicating allele flow among genotypes. The highest genetic differentiation was observed between clusters G2 and G4 (Fst = 0.1253). On the basis of structure analysis, genotypes in cluster G5 exhibited similar genetic make-up. A genome-wide association study (GWAS) identified a 490 bp locus of the SRAP 49 marker as highly effective and informatice. This locus was broadly associated with fresh root yield (FW) and dry root yield (DW) across individual and pooled environments. The positive correlation between these traits suggests simultaneous improvement is feasible. This study highlights the importance of genetic diversity for enhancing root yield and provides valuable insights for the genetic improvement of ashwagandha.

Screening and Identification of Aluminium Toxicity Tolerant Lentil (Lens culinaris Medik.) RILs based on Root Growth Studies and Organic Acid Exudation under Hydroponics

Background: Aluminium (Al) stress is among the prime limitations of crop production including Lentil, in acidic soils as Al solubilizes into phytotoxic forms at low pH causing root growth inhibition, minimizing plant-vigor and yield. The current study was performed to identify the Al tolerant RILs based on root-regrowth studies, short term growth culture and organic acid exudation in reaction to Al toxicity under hydroponics. Methods: The study involved screening for Al toxicity tolerance in recombinant inbred lines (RILs) population of lentil through root re-growth studies, short term growth response method under hydroponics treated with toxic concentration of Al (148 µM), organic acid exudation using HPLC and correlation analysis among the traits. Result: ANOVA for root and shoot traits revealed presence of highly significant genotypic differences for all the traits. High GCV along with high H2bs and GA% were observed for the traits revealing the influence of additive genes and suggested reliable selection of these traits for Al toxicity tolerance. Citric acid was exudated in highest amount in all the genotypes and was positively and significantly correlated with RRG. Based on the hydroponics study and organic acid exudation, RILs identified as tolerant were LRIL-10, LRIL-37, LRIL-68, LRIL-96, LRIL-97, LRIL-113, LRIL-125, LRIL-133, LRIL-143, LRIL-144 and LRIL-148. With further evaluation, these RILs may serve as important Al toxicity tolerant varieties suitable for acidic soil conditions. Also, these lines may serve as donors of Al toxicity loci and mapping of Al tolerance genes.

Optimizing nitrogen fertilizer for improved root growth, nitrogen utilization, and yield of cotton under mulched drip irrigation in southern Xinjiang, China

The root system plays a crucial role in water and nutrient absorption, making it a significant factor affected by nitrogen (N) availability in the soil. However, the intricate dynamics and distribution patterns of cotton (Gossypium hirsutum L.) root density and N nutrient under varying N supplies in Southern Xinjiang, China, have not been thoroughly understood. A two-year experiment (2021 and 2022) was conducted to determine the effects of five N rates (0, 150, 225, 300, and 450 kg N ha−1) on the root system, shoot growth, N uptake and distribution, and cotton yield. Compared to the N0 treatment (0 kg N ha−1), the application of N fertilizer at a rate of 300 kg N ha−1 resulted in consistent and higher seed cotton yields of 5875 kg ha−1 and 6815 kg ha−1 in 2021 and 2022, respectively. This N fertilization also led to a significant improvement in dry matter weight and N uptake by 32.4% and 53.7%, respectively. Furthermore, applying N fertilizer at a rate of 225 kg N ha−1 significantly increased root length density (RLD), root surface density (RSD), and root volume density (RVD) by 49.6–113.3%, 29.1–95.1%, and 42.2–64.4%, respectively, compared to the treatment without N fertilization (0 kg N ha−1). Notably, the roots in the 0–20 cm soil layers exhibited a stronger response to N fertilization compared to the roots distributed in the 20–40 cm soil layers. The root morphology parameters (RLD, RSD, and RVD) at specific soil depths (0–10 cm in the seedling stage, 10–25 cm in the bud stage, and 20–40 cm in the peak boll stage) were significantly associated with N uptake and seed cotton yield. Optimizing nitrogen fertilizer supply within the range of 225–300 kg N ha−1 can enhance root foraging, thereby promoting the interaction between roots and shoots and ultimately improving cotton production in arid areas.

Integrated deep banding and fertigation of phosphorus improves cotton yield by regulating root spatial distribution and growth

Context or problemTraditionally, 100 % phosphorus (P) fertilizer application as a band at various depths before sowing significantly influenced crop root growth and yield by reducing P fixation and optimizing its spatial distribution. However, with the advent of drip fertigation in Xinjiang, China, P fertilization practices have shifted from 100 % basal to a combination of basal and fertigation for enhanced P nutrition in cotton. Despite this, the impact of pre-sowing P band application on cotton growth under drip fertigation remains unclear. Objective or research questionThis study aimed to determine the optimal P fertilizer banding depth for cotton under a drip fertigation system. MethodsField trials were conducted comparing different basal P fertilizer application depths (5 cm, 15 cm, and 25 cm, denoted as D5, D15, and D25, respectively) with 50 % of the P rate and the remaining 50 % applied as topdressing via drip fertilization. A control (CK) involving 50 % broadcasted P fertilizer and 50 % topdressed P was included. The study focused on the effects of P application depth on soil P availability, root growth patterns, P utilization, and cotton yield. ResultsAt the boll opening stage, the D15 treatment exhibited a significant 18.69 %-49.76 % increase in available phosphorus in the 10–40 cm soil layer compared to the CK. During the peak boll to boll opening stage, the D15 treatment significantly outperformed the CK in terms of total root biomass density (11.62 %-17.54 %), total root length (16.75 %-24.81 %), total root surface area (23.07 %-37.59 %), and total root volume (20.69 %-26.23 %). Moreover, root activity and growth parameters were notably higher in the D15 treatment within the 10–40 cm soil layer. ConclusionsApplying 50 % of the P fertilizer as a band at a 15 cm depth before planting drip-irrigated cotton is optimal. This practice enhances soil P availability, stimulates root growth and distribution, and ultimately improves P utilization and cotton yield. Implications or significanceBanding P fertilizer at a 15 cm depth in combination with drip fertigation demonstrates superior yield benefits. This technology offers a novel approach to fertilizer application, enhancing nutrient use efficiency and crop productivity in drip-irrigated systems.

Artificial Neural Network Model for Predicting Carrot Root Yield Loss in Relation to Mechanical Heading

Modelling and predicting agricultural production processes have high cognitive and practical values. Plant growth, the threat of pathogens and pests, and the structure of agricultural machinery treatments are mostly non-linear, measurable processes that can be described mathematically. In this paper, a multiple regression analysis was carried out in the first step to check the non-linearity of the data and yielded a coefficient of determination of R2 = 0.9741 and the coefficient of determination corrected for degrees of freedom was R2adj = 0.9739. An artificial neural network model, called CH-NET, is then presented to predict the yield loss of carrot roots by leaving root mass in the field during harvest at the mechanical heading stage. The proposed network model has an architecture consisting of an input layer, three hidden layers with 12 neurons each, and an output layer with one neuron. Twelve input criteria were defined for the analysis and testing of the network, eight of which related to carrot root parameters and four to the heading machine. The training, testing, and validation database of the CH-NET network consisted of the results of field trials and tests of the operation of the patented (P.242097) root heading machine. The proposed CH-NET neural network model achieved global error (GE) values of 0.0931 t·ha−1 for predicting carrot root yield losses for all twelve criteria adopted. However, when the number of criteria is reduced to eight, the error increased to 0.0991 t·ha−1. That is, the prediction was realised with an accuracy of 90.69%. The developed CH-NET model allows the prediction of economic losses associated with root mass left in the field or contamination of the raw material with undercut leaves. The simulations carried out showed that minimum root losses (0.263 t·ha−1) occur at an average root head projection height of 38 mm and a heading height of 20 mm from the ridge surface.

YIELD AND QUALITY RESPONSES OF SOYBEAN (Glycine max. L. Merr.) VARIETIES INOCULATED WITH RHIZOBIA STRAINS UNDER DROUGHT STRESS

The aim of this study was to investigate the effects of nodule formation and nodulation performance of Rhizobia bacteria on yield and quality in soybean roots under limited water application conditions in soybean varieties depending on climate change. In this study, 4 different irrigation applications (limited vs irrigated: 25%, 50%, 75%, 100%), 2 soybean varieties (Cinsoy and Altınay) and 3 different Rhizobia inoculants (Control, AZOTEK-2, USDA-110) were applied for two years (2020-2021) in order to determine the yield and quality characteristics of soybean. The experiment was established according to randomized complete block split-split plots experimental design with 3 replications. In the experiment, the main factor was Rhizobia inoculant treatments, the first sub-factor was soybean varieties, and the second sub-factor was irrigation applications. Within the scope of the study, yield and quality parameters such as plant height (cm), first pod height (cm), number of pods plant-1, number of seeds pod-1, seed yield (kg ha-1), 1000 seed weight (g), leaf area (cm2 plant-1), seed crude protein (%) and oil content (%) were examined. It was concluded that irrigation and inoculant applications and combinations of these factors had significant effects on yield parameters of soybean varieties. The study revealed that there was no discernible nodulation development observed in soybean roots under both irrigated and limited irrigation conditions. It was determined that under conditions of limited irrigation combined with high temperature conditions, the growth of the soybean was significantly impacted, resulting in a notable reduction in yield and leaf area but this was not observed in the quality characteristics.