Shoot Yield Research Articles

Potassium Application Enhanced Plant Growth, Mineral Composition, Proximate and Phytochemical Content in Trachyandra divaricata Kunth (Sandkool).

Wild leafy vegetables are commonly included in the diet of people in rural homesteads. Among various wild edible vegetables in South Africa, Trachyandra divaricata (Sandkool) is one of the most abundant but underutilized due to the dearth of literature on its cultivation and nutritional value. In the present study, the effect of potassium application and pruning on growth dynamics, mineral composition, and proximate and phytochemical content in T. divaricata were evaluated. Treatments consisted of three potassium concentrations (0.0072, 0.0144, and 0.0216 M) supplemented in the form of potassium sulphate (K2SO4) with four pruning levels (unpruned, 5, 10, and 15 cm) applied in each treatment. The potassium doses were added to the nutrient solution, while the control treatment was sustained and irrigated with nutrient solution only. The results revealed a significant increase in flower bud yield, height, total dry and wet weight of shoots and roots, as well as ash and neutral detergent fibre in plants irrigated with 0.0072 M of K2SO4 without pruning. Conversely, chlorophyll content and Ca were comparable among treatments, while the highest yield of Na, P, N, and Zn was recorded in treatment 100 mL of K2SO4 with 10 cm pruning. Likewise, the highest antioxidant value (Polyphenols, Flavonol and DPPH) was obtained from plants irrigated with 0.0072 M of K2SO4 with 10 cm pruning. Based on these findings, T. divaricata is a promising leafy vegetable as a minimum dose (0.0072 M) of K with moderate pruning optimised its productivity in terms of growth, biomass parameters, nutritional content, and antioxidant potential. Due to its rich nutritional value, the plant should be domesticated and studied further for its potential nutraceutical benefits.

Deciphering the Ramet System of a Bamboo Plant in Response to Intensive Management

Intensive management is a common practice in bamboo plantations to ensure higher shoot yields. However, the effects of these management practices on ramet systems are understudied. A pot experiment was conducted to explore the process of propagation for potted bamboo seedlings (Phyllostachys praecox C. D. Chu et C. S. Chao “Prevernalis”) from a single mother bamboo to a ramet system exposed to a chronosequence of intensively managed bamboo forest soils. The ramet system of potted bamboo seedlings reached seven branching grades after two growth cycles. During ramet system expansion, the rhizome length and rhizome internodes decreased with increasing branching grade and the extension of intensive management periods. In the bud bank for each branching grade, the front branching grade was dominated by the bud output, which was conducive to consolidating the occupied living space. The back branching grade was dominated by bud input to continue rhizome penetration. With increasing branching, the mulching soil significantly inhibited rhizome bud germination and dormant bud accumulation. The mulching soil was not conducive to branch expansion in the ramet system, and ramet system expansion was predominantly based on the branching of the rhizome modules. With increasing branching and the extension of intensive management periods, rhizome branches decreased markedly. Our findings indicate that bamboo mulching inhibits branching and causes a differential reaction in branching types. The long-term mulching of bamboo forest soil was not conducive to the healthy and sustainable growth of bamboo. These results provide a basis for further research on the relationship between the bamboo ramet system and its productivity, as well as the population construction and maintenance mechanisms of bamboo ramet systems in the field.

Phenotypic diversity and selection in biofortified cassava germplasm for yield and quality root traits

Increasing carotenoid content and improving other root quality traits has been the focus of cassava biofortification. This study aimed to (i) evaluate the genetic variability for total carotenoid content (TCC), as well as for root yield and root quality attributes; (ii) estimate potentially useful correlations for selection; and (iii) select parents for breeding and estimate the genetic gain. Data from 2011 to 2020 of 265 cassava genotypes with cream and yellow roots were analyzed for dry matter content (DMC), shoot yield, fresh root yield (FRY), dry root yield (DRY), harvest index, average number of roots per plant, starch content, root pulp color, cyanogenic compounds, and TCC. The best linear unbiased predictions showed great phenotypic variation for all traits. Six distinct groups were formed for productive characteristics of root quality, mainly TCC, DMC and FRY. Only TCC showed high broad-sense heritability ({h}^{2}= 0.72), while the other traits had low to medium magnitude (0.21 ≤ {h}^{2} ≤ 0.60). TCC was strongly correlated with pulp color (r = 0.70), but null significance for DMC. The network analysis identified a clear separation between the agronomic and quality attributes of cassava roots. The selection of the 30 genotypes for recombination in the breeding program has the potential to raise TCC by 27.05% and reduce the cyanogenic compounds content by 23.03%, in addition to increasing FRY and DRY by 22.72% and 22.95%, respectively. This is the first consolidated study on the potential of germplasm for the development biofortified cassava cultivars in Brazil.

Immobilization of chromium bioavailability through application of organic waste to Indian mustard (Brassica juncea) under chromium-contaminated Indian soils.

Industrialization results in production of large volume of wastewaters, and disposing of them become a serious problem. The wastewaters may have range of heavy metals, which have an impact on soil and plant health. The objective was to evaluate the influence of farm yard manure (FYM) and pressmud (PM) applications on Indian mustard growth and chromium (Cr) uptake in tannery effluent irrigated Cr-contaminated soil. Soil was collected from the tannery effluent irrigated fields (chromium contaminated) of Shekhpura village of Kanpur, India. A pot culture experiment was carried out by growing Indian mustard (Brassica juncea) var. RH 749 on the Cr-contaminated soil with application of different levels and combinations of FYM and PM (at 0, 2.5, and 5gkg-1 each). Biomass yield, Cr uptake, bioconcentration factor (BCF), transfer factor (TF), transfer efficiency (TE), and Cr removal indices were examined. Higher doses of FYM and PM resulted in reduction of Cr concentrations in shoot (6.60 to 2.50µgg-1) and root (27.27 to 9.43µgg-1); and absorption in plant tissues and had improved total dry matter yield (14.56 to 30.94g pot-1). The use of FYM and PM had a substantial (p ≤ 0.05) impact on phytoremediation parameters like BCF (0.128 to 0.045), TE (59.61 to 64.51%), and Cr removal (0.65 to 0.51%). Combined application of FYM (5gkg-1) and PM (5gkg-1) had enhanced the dry matter yield of shoot (12.51 to 26.40g pot-1) and root (2.05 to 4.54g pot-1) and reduced the Cr uptake (138.54 to 108.79mg pot-1) than the individual amendment addition of FYM (138.52 to 135.89mg pot-1) and PM (126.02 to 130.52mg pot-1). Combined application of FYM (5gkg-1) and PM (5gkg-1) could be beneficial for remediation of Cr-contaminated areas for cultivation of crops.

Agronomic Performance of Kale (Brassica oleracea) and Swiss Chard (Beta vulgaris) Grown on Soil Amended with Black Soldier Fly Frass Fertilizer under Wonder Multistorey Gardening System

The wonder multistorey garden (WMSG) is an innovative vertical farming system tailored for urban settings that can be constrained by the irrigation regime, and by types and levels of fertilizer application. This study evaluated the effects of applying NPK fertilizer and black soldier fly frass fertilizer (BSFFF) under different irrigation regimes on the growth, yield, and pest infestation of kale (Brassica oleracea) and Swiss chard (Beta vulgaris). The fertilizers were applied at rates equivalent to 371 kg N ha−1. For each crop, the BSFFF or NPK was applied to supply 100% of the N required (100% BSFFF), and then a combination of BSFFF and NPK was applied so that each fertilizer supplied 50% of the N required (50% BSFFF + 50% NPK). Crops’ water requirements were provided using three irrigation regimes: daily, every two days, and every three days. The control treatment was not amended with any fertilizer, while water was provided ad libitum. The results revealed that the irrigation regime significantly affected the leaf production of both vegetables. Irrigation regimes significantly influenced kale plant height, where plants provided with water daily achieved the highest average heights of 20 cm, 46 cm, and 54 cm at 14, 28, and 42 days after transplanting (DAT), respectively. Furthermore, the application of 100% BSFFF produced kale with significantly higher plant heights (55 cm) and number of leaves (9.9 leaves) at 42 DAT compared to other treatments. The interaction between irrigation regimes and fertilizer significantly influenced kale height at 14 DAT and 42 DAT. Use of daily irrigation regime and 100% BSFFF produced the tallest kale plants of 59 cm at 42 DAT. Application of 50% BSFFF + 50% NPK or 100% BSFFF with daily irrigation achieved the highest values of kale and Swiss chard leaf chlorophyll concentration, recorded at 42 DAT. Fertilizer application significantly affected pest population, with the lowest pest infestation being recorded from kale and Swiss chard grown in soil amended with BSFFF. The application of 100% BSFFF or NPK, together with daily irrigation, significantly increased the fresh shoot weight and leaf dry matter of kale and Swiss chard, as compared with the control. The fresh shoot yields of kale and Swiss chard achieved through using a combination of 100% BSFFF and daily irrigation were 14–69% and 13–56% higher than those of NPK, respectively. The same treatment combination also produced kales and Swiss chard with 8–73% and 16–81% higher leaf dry matter compared to NPK, respectively. It was noted that soil amendment with BSFFF maintained higher values of kale (41–50%) and Swiss chard (33–49%) leaf dry matter compared with NPK treatments, during periods of water stress. Our study has demonstrated the high potential of single (100% BSFFF) or combined applications of BSFFF (50% BSFFF + 50% NPK) with a daily irrigation regime to improve the growth, yield, and pest management in Swiss chard and kale under vertical farming. Our study advocates for the scaling of WMSG and BSFFF for sustainable food systems in urban settings.

Contribution of tillers to maize yield stability at low plant density

AbstractOne of the main challenges of using low plant densities in restrictive and variable environments is to maximize the use of resources in better‐than‐expected years. In this context, tillering could be an alternative to increase reproductive and vegetative plasticity. The objectives of this study were to (a) characterize the correlation between environmental conditions, tiller traits, crop grain yield, and grain yield advantages due to tillers; (b) determine the grain yield response to tillering (i.e., grain yield difference between tillered and nontillered crops) for a wide range of environments; and (c) to evaluate the effect of tiller presence on grain yield of the main shoot, considering its effect on the apical and subapical ears. Tillered and nontillered crops were evaluated under rainfed conditions during two seasons (2018–2019 and 2019–2020). These experiments were carried out at 11 sites in the southern Argentinean Pampas, varying sowing date (22 Oct. to 5 Dec.), plant density (2–3 plants m−2), genotype (AX7784 and AX7761), and soil depth. Grain yield (3.2–11.9 Mg ha−1) was correlated with tillers productivity, mainly explained by postflowering precipitations. The contribution of tillers to grain yield was more proportional than their consequent yield depression at the main shoot. Tillers either increased (3 sites) or maintained (8 sites) grain yield, and their contribution increased as the environment improved without any detrimental effect in the most restrictive environments. Tillering has the potential for increasing resource (radiation, water, nitrogen) use efficiency under low plant density strategies adopted for restrictive environments.

Cadmium phytoremediation potential of Brassica genotypes grown in Cd spiked Loamy sand soils: Accumulation and tolerance.

Phytoremediation acts as an efficient methodology for management of toxic elements spiked soils. The accumulation and tolerance potential of hyper-accumulator plants for toxic elements act as an index for in-situ removal of toxic elements. Extraction of cadmium (Cd) through its accumulation in harvestable parts of plants has attracted attention as the economic and environment friendly technique. Brassica genotypes have greater potential to accumulate Cd when grown in Cd spiked soils. Therefore, for evaluation of comparative efficiency of three Brassica genotypes (B. juncea, B. campestris and B. napus) in phytoremediation of Cd spiked soils, a pot study was carried out in Cd contaminated soil with 6 levels as 0, 5, 10, 20, 40, and 80mgkg-1 soil. Results indicated that dry biomass production of Brassica genotypes declined with the enhanced Cd contamination in soil. The reduction in grain and shoot yield varied from 2.87 to 1.85 and 11.85 to 8.00g pot-1 with increased Cd contamination from 5 to 80mgkg-1 soil. Similarly, increased levels of Cd contamination resulted in enhanced concentration and accumulation in grains as well as shoots of all Brassica genotypes. Among Brassica genotypes, B. juncea recorded the highest production of dry biomass (12.8g pot-1), Cd accumulation (736.0μg pot-1). Also, the bioaccumulation coefficient and tolerance index indicated that B. juncea is the most tolerant genotype to Cd contamination in soil. Therefore, B. juncea could act as the most potential genotypes for decontamination of Cd spiked soils by preventing its entry into food chain.

Can aeration improve bamboo soil fertility of soil below bamboo and fungal diversity under mulching conditions?

AbstractAeration can alleviate soil hypoxia stress of Phyllostachys praecox bamboo under mulching conditions, but how aeration affects soil properties, soil fungal community structure, and bamboo development is unclear. We studied the responses of soil properties, fungal community structure, bamboo shoots, and rhizome growth to organic mulching (TM), mulching with aeration (TA1 and TA2), and no‐mulching treatments (CK) from a field experiment in March and July, 2019. During the mulching period (March), the aeration improvement treatment (TA2) improved soil O2 content, bamboo shoots yield, and soil nutrient availability significantly when compared with TM. TA2 treatment showed significantly higher relative abundances of the genus Trichoderma and functional group endophyte than TM treatment, which might be conducive to soil nutrient transformation and bamboo growth. The TA2 treatment had higher fungal diversity indices than that of the TA1 treatment, suggesting that optimal aeration conditions enhance soil fungal diversity. The fungal community structure also showed strong temporal dynamics in all treatments. Mantel test results indicated soil O2 is the primary factor driving fungal community structure under mulching conditions, while has no impact on the fungal community in summer; fungal community structure was primarily controlled by soil pH in summer. Structural equation model revealed soil NO3−‐N content was responsible directly for bamboo rhizome growth and shoot yield. Our results indicate short‐term mulching is beneficial to soil nutrients improvement and bamboo yield increase, while rational aeration can further facilitate sustainable plantation development under hypoxic soil conditions.

Effects of Strong Shading Treatment on Plucked New Shoot Yield, Leaf Color, Free Amino Acid Content, and Unrefined Tea Quality in Tea Cultivars Recommended by the Shizuoka Prefecture

Effects of Strong Shading Treatment on Plucked New Shoot Yield, Leaf Color, Free Amino Acid Content, and Unrefined Tea Quality in Tea Cultivars Recommended by the Shizuoka Prefecture

Effect of temperature stress on Brassica rapa genotypes during germination and reproductive growth

The effect of temperature stress on the reproductive development and yield of five Brassica rapa was studied in a controlled growth chamber. The seeds of five Brassica genotypes namely BARI Sarisha-6, Tori 7, Kallayania, BARI Sarisha-9 and BINA Sarisha-4 were grown under day/night temperatures at 22/170C until early flowering or early siliqua development stage. The high temperature stress i.e., 28 /170C or 35/170C, both at early flowering stage and early siliqua formation stage were imposed for 7d and then allowed to recover at 22/170C for normal growth. Shoot dry matter accumulation varied with temperature and genotype. The highest shoot dry matter was recorded by Kallayania followed by BARI Sarisha-9. The optimum day temperature for seed yield of the main shoot showed closer to 280C. The largest seeds were produced in the 22/170C, the size, however, remained similar with 28/170C temperature stress. During this temperature regime, the highest seed yield was observed with BARI Sarisha-6 while BARI Sarisha-9 produced the lowest seed yield. Severe temperature stress (35/170C) reduced seeds per siliqua and 1000 seed weight in all genotypes. Maximum pollen viability and germination were recorded at 200C by Kallayania followed by Tori 7 at 250C. However, the temperature above 300C reduced pollen viability and germination for all the genotypes. In another set of treatments, the high temperatures exposure (28/230C) for 5d reduced oil content and increased protein concentrations. Plant exposed to 25/200C temperature stress showed significant changes in oleic, linoleic, and linolenic acids. The levels of saturated fatty acids were similar across the five genotypes in the control treatment, but palmitic acid and stearic acids increased with the temperature. Bangladesh J. Agri. 2019-2021, 44-46: 19-29

Newly Discovered Alleles of the Tomato Antiflorigen Gene SELF PRUNING Provide a Range of Plant Compactness and Yield.

In tomato cultivation, a rare natural mutation in the flowering repressor antiflorigen gene SELF-PRUNING (sp-classic) induces precocious shoot termination and is the foundation in determinate tomato breeding for open field production. Heterozygous single flower truss (sft) mutants in the florigen SFT gene in the background of sp-classic provide a heterosis-like effect by delaying shoot termination, suggesting the subtle suppression of determinacy by genetic modification of the florigen–antiflorigen balance could improve yield. Here, we isolated three new sp alleles from the tomato germplasm that show modified determinate growth compared to sp-classic, including one allele that mimics the effect of sft heterozygosity. Two deletion alleles eliminated functional transcripts and showed similar shoot termination, determinate growth, and yields as sp-classic. In contrast, amino acid substitution allele sp-5732 showed semi-determinate growth with more leaves and sympodial shoots on all shoots. This translated to greater yield compared to the other stronger alleles by up to 42%. Transcriptome profiling of axillary (sympodial) shoot meristems (SYM) from sp-classic and wild type plants revealed six mis-regulated genes related to the floral transition, which were used as biomarkers to show that the maturation of SYMs in the weaker sp-5732 genotype is delayed compared to sp-classic, consistent with delayed shoot termination and semi-determinate growth. Assessing sp allele frequencies from over 500 accessions indicated that one of the strong sp alleles (sp-2798) arose in early breeding cultivars but was not selected. The newly discovered sp alleles are potentially valuable resources to quantitatively manipulate shoot growth and yield in determinate breeding programs, with sp-5732 providing an opportunity to develop semi-determinate field varieties with higher yields.

Genome-wide association study and selection for field resistance to cassava root rot disease and productive traits

Cassava root rot disease is caused by a complex of soil-borne pathogens and has high economic impacts because it directly affects the tuberous roots, which are the main commercial product. This study aimed to evaluate cassava genotypes for resistance to root rot disease in a field with a previous history of high disease incidence. It also aimed to identify possible genomic regions associated with field resistance based on genome-wide association studies. A total of 148 genotypes from Embrapa Mandioca and Fruticultura were evaluated over two years, including improved materials and curated germplasms. Analysis of phenotypic data was conducted, as well as a genomic association analysis, based on the general linear model, mixed linear model, and fixed and random model circulating probability unification. The observed high disease index (ω) was directly correlated with genotype survival, affecting plant height, shoot yield, and fresh root yield. The genotypes were grouped into five clusters, which were classified according to level of root rot resistance (i.e., extremely susceptible, susceptible, moderately susceptible, moderately resistant, and resistant). The 10 genotypes with the best performance in the field were selected as potential progenitors for the development of segregating progenies. Estimates of genomic kinship between these genotypes ranged from -0.183 to 0.671. The genotypes BGM-1171 and BGM-1190 showed the lowest degree of kinship with the other selected sources of resistance. The genotypes BGM-0209, BGM-0398, and BGM-0659 showed negative kinship values with most elite varieties, while BGM-0659 presented negative kinship with all landraces. A genome-wide association analysis detected five significant single nucleotide polymorphisms related to defense mechanisms against biotic and abiotic stresses, with putative association with fresh root yield in soil infested with root rot pathogens. These findings can be utilized to develop molecular selection for root rot resistance in cassava.

Contribution of the carbonized rice husk added to the substrate in the production of vegetable seedlings

The carbonized rice husk (CRH) is an agro-industrial residue with great potential for use in mixtures with other substrates for the production of vegetable seedlings. Thus, the purpose of this study was to evaluate the effect of the addition of CRH to the commercial substrate for the production of greenhouse seedlings. The evaluated vegetables were lettuce, broccoli and mustard, cultivated in polystyrene foam (Styrofoam®) trays. Five treatments were evaluated: 100% of the commercial substrate (CS); 25% of CRH + 75% of CS; 50% of CRH + 50% of CS; 75% CRH + 25% CS; and 100% CRH, in a completely randomized design with twelve replicates. The substrates were evaluated for their physical and chemical characteristics. The morphometric evaluations were: number of leaves per plant, plant height, shoot fresh matter yield, root length, and shoot and root dry matter yield. The data were submitted to regression analysis, and the homogeneity of the variance between the experiments was confirmed by the Cochran test. With the addition of CRH to the substrate, there was an increase in total porosity and P content and a reduction in density, water holding capacity, cation exchange capacity, electrical conductivity, and N, K, S, Ca and Mg contents. The carbonized rice husk added to the commercial substrate is a viable alternative for the production of lettuce, broccoli and mustard seedlings. The quality of the vegetable seedlings was higher when there was a 25% CRH + 75% CS mixture.

TCP Transcription Factors Involved in Shoot Development of Ma Bamboo (Dendrocalamus latiflorus Munro).

Ma bamboo (Dendrocalamus latiflorus Munro) is the most widely cultivated clumping bamboo in Southern China and is valuable for both consumption and wood production. The development of bamboo shoots involving the occurrence of lateral buds is unique, and it affects both shoot yield and the resulting timber. Plant-specific TCP transcription factors are involved in plant growth and development, particularly in lateral bud outgrowth and morphogenesis. However, the comprehensive information of the TCP genes in Ma bamboo remains poorly understood. In this study, 66 TCP transcription factors were identified in Ma bamboo at the genome-wide level. Members of the same subfamily had conservative gene structures and conserved motifs. The collinear analysis demonstrated that segmental duplication occurred widely in the TCP transcription factors of Ma bamboo, which mainly led to the expansion of a gene family. Cis-acting elements related to growth and development and stress response were found in the promoter regions of DlTCPs. Expression patterns revealed that DlTCPs have tissue expression specificity, which is usually highly expressed in shoots and leaves. Subcellular localization and transcriptional self-activation experiments demonstrated that the five candidate TCP proteins were typical self-activating nuclear-localized transcription factors. Additionally, the transcriptome analysis of the bamboo shoot buds at different developmental stages helped to clarify the underlying functions of the TCP members during the growth of bamboo shoots. DlTCP12-C, significantly downregulated as the bamboo shoots developed, was selected to further verify its molecular function in Arabidopsis. The DlTCP12-C overexpressing lines exhibited a marked reduction in the number of rosettes and branches compared with the wild type in Arabidopsis, suggesting that DlTCP12-C conservatively inhibits lateral bud outgrowth and branching in plants. This study provides useful insights into the evolutionary patterns and molecular functions of the TCP transcription factors in Ma bamboo and provides a valuable reference for further research on the regulatory mechanism of bamboo shoot development and lateral bud growth.

Characterization of Young Shoot Population, Yield, and Nitrogen Demands of Tea (Camellia sinensis L.) Harvested under Different Standards

The quality of green tea is greatly influenced by the harvest standards for young shoots. The present field experiment was conducted to characterize the young shoot populations, yields, and nitrogen (N) demands of tea plants subjected to four different harvest standards, i.e., buds with one, two, or three young expanding leaves (referred to as B1L, B2L, and B3L, respectively) and a combination of B1L and B3L (B1L/B3L) throughout the year. Weight per shoot was closely related to the number of expanding leaves and was greater in B3L than B1L and B2L, and also greater in summer and autumn than in spring, whereas B1L revealed the greatest young shoot density and highest N concentration. Annual shoot yield and shoot N content were largest in B3L and decreased in the following order: B3L > B2L ≈ B1L/B3L > B1L. However, in the early spring the shoot density, yield, and shoot N content of B1L were much higher than those of B3L. The harvest of B3L significantly reduced the biomass of brown roots and its ratio against the above-ground biomass compared to other harvest standards, suggesting a decreased allocation of carbon to the root system due to seasonal removal. The N dilution curve (Nys = a × Yysb, where Nys is the shoot N content and Yys is the shoot yield) of spring tea differed markedly from those of summer and autumn teas, suggesting different coordination properties for shoot growth and N supply among the seasons. The annual harvest index (NHI) measured by 15N traces ranged between 0.18 and 0.23, indicating relatively low N allocation to young shoots, whereby large proportions (58.2–66.9% of the total 15N absorption) remained in the plant at the end of the experiment. In conclusion, the seasonal distribution of the shoot density, weight per shoot, yield, and N demands vary with harvest standards and highlight the importance of N precision management in tea production to be finely tuned to meet the changes in harvest season and requirements.

Effect of levels and types of organic, biological, and chemical fertilizers on morphological traits, yield, and uptake rate of elements in Satureja mutica

Satureja species are of great economic and medical importance due to their high content of essential oils and use in food, cosmetics, and pharmaceutical industries. Due to the domestication and introduction of Satureja mutica cultivars, for the first time and the lack of comprehensive research on its cultivation, the need for research on the nutritional needs of this plant and the introduction of suitable fertilizer treatments that can be used by farmers is important. This experiment was carried out in 2018 and 2019 in field conditions using randomized complete blocks with three replications and 21 treatments in the Research Institute of Forests and Rangelands. The results of mean comparisons of fertilizer treatments (mean of two years) showed that the highest plant height, with 88 and 80 cm, was related to cow manure treatments of 30 and 60 tons per hectare, respectively. The highest flowering shoot yield, with 4427, 4266, and 4113 kg ha−1, was obtained from N50P25K25 + vermicompost10 and N50P25K25 + cow manure60 and N50P25K25 + cow manure30 treatments in the second year, respectively. The lowest yield of the flowering shoot (849 kg ha−1) belonged to Pseudomonas putida treatment. The highest leaf yield, with 2556 and 2441 kg ha−1, was obtained from N25P25K25 + vermicompost10 and N25, P25, K25 +cow manure60 treatments, respectively. According to the results, the highest nitrogen content, with 2.44 and 2.32 g/100 g, was obtained from the cow manure30 treatment in the first and second year, respectively. The maximum nitrogen uptake with 94.43 kg ha−1 was obtained from N50, P25, K25 + vermicompost10. The lowest nitrogen uptake at 24 kg ha−1 was related to Pseudomonas putida treatment. The mean comparison of two years showed that the highest essential oil percentage (2.11 g/100 g) and yield (79.27 kg ha−1) were obtained from the second year compared with the first year. Carvacrol, γ-terpinene, thymol, and p-cymene were the major components in the essential oil. The results showed that the combined treatments of chemical fertilizers with animal manure and vermicompost are suitable treatments to increase the yield of different organs and essential oil yield in field conditions.

Closing the circle for urban food waste anaerobic digestion: The use of digestate and biochar on plant growth in potting soil

Food waste can be used via anaerobic digestion (AD) to produce biogas. The liquid by-product (digestate) contains nitrogen (mainly as ammonium) which is susceptible to N loss as a fertiliser and also faces logistical constraints for agricultural use. Biochar can adsorb and retain nutrients and alter microbial N-cycling processes. We investigated the use of digestate as a nutrient source and its interactions with biochar when applied to potting mix targeted for localised urban use. Tomato (Solanum lycopersicum L.) plants were grown for 45 days in potting mix amended with five rates of food-waste-derived digestate (0, 2, 4, 6, 8 and 10% v/v), with and without biochar (10% v/v). At harvest, plant growth parameters and potting soil characteristics were measured. The rhizosphere bacterial community was profiled by amplicon sequencing followed by an in-silico analysis of putative functional genes. Plant biomass and shoot N concentration increased with digestate addition in a typical nutrient dose-response curve. While growth lagged when digestate was combined with biochar, both treatments reached a similar maximum shoot yield. Biochar application decreased soil mineral N content and two putative ammonium nitrification cycling genes, AmoA and AmoB, which prevent the conversion of NO3- from NH4+. Rhizosphere bacteria beta-diversity separated into two distinct clusters, with and without biochar, at all levels of digestate. Addition of biochar with digestate decreased the availability of soil mineral N by decreasing the mineralisation of nitrogen which likely reduced the risk of N loss. The rhizosheath bacterial community mediated this effect. Further quantification of these processes may aid in optimising of the benefits for the environment and plant growth from the transformation of blended organic urban wastes into organic fertilisers for potting soils.

The inorganic nitrogen fertilizer equivalency of hairy vetch (Vicia villosa Roth) as a winter green manure in Kanto and Tohoku district, Japan

ABSTRACT It is well known that legume green manure (GM) supplies nitrogen (N) to succeeding crops. However, in Japan, there are few experimental field studies that have quantitatively evaluated the effect of GM on the N supply. To estimate the inorganic N fertilizer equivalency of GM for the succeeding corn crop, two field experiments were conducted in 2012 at Morioka, Tohoku district (cool climate region) and in 2014 at Nasushiobara, Kanto district (warm temperate region). Each experiment had a split-plot design with a factorial arrangement of two cropping systems, hairy vetch [HV; Vicia villosa Roth] GM and conventional cultivation, with four N fertilizer treatments (0, 75, 150, and 225 kg N ha−1). In both sites, GM increased the N uptake and, as a result, the shoot yield of the succeeding forage (silage) corn. The apparent N recovery rates of HV shoot were 64% at Morioka and 24% at Nasushiobara. The inorganic N fertilizer equivalency rates of HV shoot were 82% at Morioka and 104% at Nasushiobara. In conclusion, by introducing HV as a GM, we can reduce the amount of inorganic N fertilizer applied to the succeeding corn crop with the same amount as at least 80% of N uptake in HV shoot.

Yield and Quality of Some Tropical Sugarbeet Genotypes Under Bangladesh Conditions

The experiment was conducted at the experimental farm of Agronomy and Farming Systems Division, Bangladesh Sugarcrop Research Institute (BSRI), Ishurdi, Pabna, Bangladesh during 2012-13 cropping season to assess the comparative performance of yield and quality of six tropical sugarbeet genotypes viz., CS 0327, HI 0473, CS 0328, HI 0044, Shubhra and Cauvery. The different genotypes showed significant differences in their yield and yield components, such as beet length, beet girth, beet yield, shoot yield, sugar yield and harvest index. The quality parameters, such as total soluble solids or brix, sucrose percentage and apparent purity percentage of sugarbeet were also different among the genotypes. Maximum beet length (31.38 cm), beet girth (36.09 cm), beet yield (75.46 t ha-1), shoot yield (38.46 t ha-1) and sugar yield (11.82 t ha-1) were found in Cauvery followed by CS 0328. In case of sugarbeet quality, the maximum total soluble solids (TSS) and sucrose percentage (21.90% and 15.68%, respectively) were recorded in Cauvery followed by the genotype CS 0328 (21.52% and 15.50%, respectively). So, it was concluded that tropical sugarbeet genotype Cauvery appeared as the best one with respect to yield and quality parameters followed by CS 0328 under Bangladesh conditions.
 Bangladesh Agron. J. 2021, 24(2): 55-61

An exploratory method to determine the plant characteristics affecting the final yield of Echium amoenum Fisch. & C.A. Mey. under fertilizers application and plant densities

Employing of advanced statistical methods to quantify agricultural information has helped to carry out targeted planning to alleviate the problems of farmers, researchers and policy section. One of these exploratory methods, is multivariate statistical analysis that examines and models the relationship between variables. Considering the importance of Echium amoenum and its use growing trend in traditional medicine and the pharmaceutical industry, also the lack of information on the correlations between its yield and morpho physiological traits, the objective of this study was to determine the causality path in which the Echium amoenum characteristics affects the yield of Echium amoenum as regards of application of organic and chemical fertilizers under different plant densities. The employed method revealed that organic fertilizers increased flower yield compared with the control. The flower yield as a result of application of compost, vermicompost and cattle manure were increased by 25, 28, and 27% compared with the control, respectively. The results of multiple regression showed that variables of plant height, shoot dry weight, flower number per plant were the main factors affected the flower yield. The relative contribution of shoot dry weight was 16 and 25% more than plant height and flower number per plant, respectively. Causality analysis identified that shoot dry weight per plant had indirect effect on flower yield in different paths, as mainly was imposed through plant height considering the path coefficients. This study suggests that optimum production of Echium amoenum with application of ecological inputs along with effective agronomical managements of the causal paths of flower yield forming, including increase in shoot yield and plant height could be achieved through an ecological cropping system with reduced costs and no health concerning due to agrochemicals residual.