Shallot production has many challenges, including the anthracnose disease caused by the pathogen Colletotrichum gloeosporioides Penz. Disease characteristics include severe twisting of leaves, neck elongation, and necrosis of leaves. This disease can cause yield loss of up to 100 percent. In addition to chemical control practices, resistant shallot varieties will be very useful in decreasing losses. However, information about existing shallot varieties resistant to C. gloeosporioides is limited. The study objectives are to identify the shallot varieties resistant to C. gloeosporioides and identify morphological characters and secondary metabolites of the leaves that may associate with the defense mechanism in shallot. Fourteen shallot varieties underwent a single factor use in a randomized block design in the field and laboratory experiments. The experiment transpired from January to June 2021. Planting healthy shallot bulbs of all genotypes in a polybag containing sterile media continued by artificial inoculation of C. gloeosporioides after the plant had 3–5 leaves. The field test showed that the Sumenep variety has the best resistant level to C. gloeosporioides, with a disease severity score of about 30.19%. On the other hand, the Blue Lancor variety is most susceptible, with a disease severity score reaching 95.05%. The study also found an indication that a possible resistance of shallots to C. gloeosporioides relates to the thickness of the palisade tissue (r =-0.8, P < 0.001), with the induced mechanism associated with the detection of the presence and increase of carbamic acid concentrations.

Keywords: Carbamic acid, defense mechanism, palisade tissue, secondary metabolite, Sumenep variety

Key findings: Identifying the resistance of leaf cellular morphology showed that palisade tissue is a character associated with shallot resistance to C. gloeosporioides.

Currently, the selection of tomatoes with a high content of biologically active substances and antioxidant properties at the large green and breaker stage is relevant since mature tomatoes cannot tolerate storage and transportation. For this purpose, 11 tomato genotypes, chosen in a preliminary study in 2018–2020 from the Genetic Collection of Plant Resources of Federal State Budgetary Scientific Institution Federal Scientific Vegetable Center (FSBSI FSVC), Moscow, Russia, and Tomato Genetics Resource Center (TGRC), the University of California, Davis, USA, for further studies during 2020–2022 for antioxidant pool changes: measuring the contents of chlorophyll, lycopene, β-carotene, ascorbic acid, and lutein. The experiment arranged in a randomized complete block design proceeded in the film unheated greenhouses. The results showed five promising tomato genotypes, i.e., VFN Hi Sugar, VS-420, Paul Robeson, Black Cherry, and VS-410. The genotype Black Cherry fruits with breaker ripeness contained 42% lycopene and 93% β-carotene, while the genotype Paul Robeson at the same stage contained 80% β-carotene. The three other tomato genotypes, viz., VFN Hi Sugar, VS-420, and Paul Robeson, also gave a higher content of ascorbic acid in the fruits at the breaker ripening stage.

Keywords: Tomato, ascorbic acid, β-carotene, chlorophyll, lutein, lycopene, total phenols

Key findings: The studied dynamics of various pigments with biological activity according to the tomato ripening stages revealed promising genotypes identified and selected for further studies.

The present study aimed to determine the genetic divergence of seven maize genotypes (Al-Maha, Sumer, Al-Fajr, Baghdad, 5018, 4 × 1 single hybrid, and 4 × 2 single hybrid) under two varied levels of nitrogen fertilization (92 and 276 kg N ha^-1). The experiment occurred in 2022 in a randomized complete block design (RCBD) with a split-plot arrangement and three replications at the College of Agricultural Engineering Sciences, University of Baghdad, Iraq. The nitrogen fertilization levels served as main plots, with the maize genotypes allocated as the subplots. The results revealed that genetic variance was higher than the environmental variance for most traits, and the coefficient of phenotypic variation was close to the genetic variation coefficient under the two levels of nitrogen fertilization. Heritability (broad sense) at the 92 kg N ha^-1 (N1 level) was the highest for traits. i.e., ear height, grains per row, grains per ear, individual plant yield, yield per unit area, days to 50% male flowering, leaf area, ear length, rows per ear, and 100-grain weight, with values of 92.556%, 90.760%, 90.123%, 95.007%, 95.007%, 88.976%, 89.974%, 88.748%, 85.521%, and 89.690%, respectively. For the N level of 276 kg ha^-1 (N2 level), the heritability in a broad sense was high for the traits, viz., days to 50% male flowering (91.546%), plant height (96.150%), ear height (91.038%), ear length (92.454%), individual plant yield (98.108%), yield in the unit area (98.108%), and plant dry weight (85.488%). The cluster analysis divided the maize genotypes into four and five cluster groups under the nitrogen fertilization level of 92 and 276 kg N ha^-1, respectively. These different groups of maize genotypes could be due to the genetic divergence among the genotypes resulting from their varied genetic makeup and origin.

Keywords: Maize (Zea mays L.), genetic diversity, nitrogen fertilization levels, heritability, broad sense, cluster analysis, yield related traits

Key findings: The presented study can identify the genetically diverged maize genotypes with some other genetic parameters, which could benefit hybridization for transferring better yield-related genes to improve grain yield through various breeding methods.

Five rice (Oryza sativa L.) cultivars (N22, Amber, Moroberekan, Kinandang Patong, and Azucena) underwent path coefficient analysis across three plant spacings (15 cm × 15 cm, 20 cm × 20 cm, and 25 cm× 25 cm) in the summer of 2017 at the College of Agricultural Engineering Sciences, University of Baghdad, Al-Jadriya, Iraq. The experiment proceeded in a randomized complete block design (RCBD) with a split-plot arrangement and three replications. The main plots included three planting distances, and the subplot comprised five varieties. The traits studied were plant height, flag leaf area, number of tillers, panicle number, length and branches, grains per panicle, 1000-grain weight, and the percentage of unfilled grains. The results showed significant (P ≤ 0.05) differences between direct and indirect and total effects. The studied traits provided negative values for the total effects except for the number of tillers and the number of panicles per plant, as these two traits reached 1.0938 and 1.0798, respectively. With the second plant spacing of 20 cm × 20 cm, the traits: plant height, number of tillers, number of panicles, and panicle length, showed the total positive effects, ranging from 0.2803 to 0.6606, with the remaining traits enunciated negative values. For the third plant spacing of 25 cm × 25 cm, the traits: panicle length, number of tillers, grains per panicle, and 1000- grain weight, exhibited positive values for the total effects, ranging from 0.623 to 1.1593.

Keywords: Rice (Oryza sativa L.), path coefficient analysis, correlation coefficient, genetic variability, plant spacing, morphological and yield-related traits, grain yield

Key findings: Significant variations among direct and indirect effects of various rice traits indicate that the panicle length, number of tillers, grains per panicle, and 1000-grain weight with a plant spacing of 25 cm × 25 cm could serve as vital selection criteria for improving the grain yield in rice.

Selected agronomic traits are the conventional approach to evaluating corn plantings. However, this approach is only some-encompassing for planting plots; hence, needing a more precise method for the evaluation. Unmanned aerial vehicles (UAVs) or drones are precision technologies that provide detailed information regarding cropping status through image analysis to make the assessment and prediction process more efficient. Therefore, using agronomic traits and drones together is a necessary approach to take. Presented research aimed to develop a productivity prediction model based on selective and precision secondary characters. The experiment happened from September to December 2021 in Tarowang Village, Takalar Regency, South Sulawesi, Indonesia. Eight maize cultivars, i.e., ADV1, Pioneer 1, Pioneer 2, NK, Bisi 18, Sinhas 1, NASA 29, and ADV2, grown and evaluated in a randomized completely block design with three replications, served as the main factor. Based on the results, the weight of 1000 grains, was a recommended agronomic trait in the evaluation and prediction of corn planting. In addition, normalized difference vegetation index (NDVI)-UAV, as part of ‘Technology 4.0’, considerably showed effectiveness in predicting maize productivity. Meanwhile, combining two variables notably have the highest accuracy in predicting corn productivity compared with their independent predictions. However, the advanced research still needs optimizing by using more maize genotypes and locations to increase the accuracy and forecast of the model.

Keywords: Agronomic traits, multivariate regression, NDVI, Technology 4.0, Zea mays

Key findings: Combining a selective agronomic trait (weight of 1000 grain) and NDVI-UAV revealed more effectiveness in evaluating the maize genotypes. This combined strategy can enhance the accuracy and precision of corn yield prediction. The multiple regression formulation from combining the two characters was 17.0486 NDVI + 0.038 weight of 1000 grain – 20.244. Moreover, the maize cultivar NK-7328 proved to be the best for cultivation in Takalar Region, Indonesia.

Zinc deficiency in cereal crops is a significant issue for human health. Rice, being a staple food crop, could cause severe zinc deficiency. The use of zinc-solubilizing bacteria (ZSB) is an ecological tactic to raise bioavailable zinc in the soil that may alleviate yield loss and, subsequently, enhance the nutritional value of rice. In the presented study, treating rice plants with plant growth-promoting rhizobacteria S. marcescens FA-4 along with the recommended dose of chemical Zn and half dose of chemical Zn ensued under pot and field conditions at the COMSATS University, Islamabad, Pakistan. The obtained data indicated an augmentation in rice growth, yield, and grain zinc content in response to the S. marcescens FA-4 inoculation with and without the chemical Zn application. The S. marcescens FA-4 significantly enhanced the grain zinc content (21.4–27.7 mg kg^-1) under the pot and (18.7–30.1 mg kg^-1) under field conditions, with 1.5 to twofold rise in superoxide dismutase (SOD) and carbonic anhydrase (CA) activity in rice compared with the control. The rice plants treated with zinc solubilizing bacteria, followed by zinc treatments gave higher grain yields of 23.4–34.1 g pot^-1 and 3.2–3.6 t ha⁻¹ in rice cultivars, Basmati 385 and Super Basmati. The S. marcescens FA-4 with a half dose of chemical Zn also increased the zinc translocation index (1.4 to 1.7) toward grains. Consistency in the performance of zinc solubilizing bacteria occurred in the pot and field conditions. Hence, a conclusion that the use of zinc solubilizing strains is an efficient approach to enhance the zinc content of rice grains and combat the problem of zinc deficiency in humans.

Keywords: Zinc-solubilizing bacteria, superoxide dismutase, carbonic anhydrase, grain zinc content, rice

Key findings: The rice growth and yield increased in response to the combination of zinc solubilizing Serratia marcescens FA-4 and half a dose of chemical Zn. The Serratia marcescens FA-4 significantly enhanced the grain zinc content under the pot and field conditions, causing a 1.5 to twofold rise in superoxide dismutase (SOD) and carbonic anhydrase (CA) activity in rice compared with the control.

Phenotypic and genotypic diversity is essential and needs more enhancement in different ways to achieve higher productivity and better quality vegetables. The presented research aimed to study the phenotypic characteristics and determine the genetic diversity of F₁ populations compared with the colchicine mutant variants in the Mercy cultivar of cucumber (Cucumis sativus L.), held from March to May 2019 at the experimental field of the Department of Agrotechnology, Islamic University of Riau, Pekanbaru, Indonesia. A total number of 144 studied plants comprised 72 from each of the two plant groups. The data recorded on various parameters attained statistical analysis using paired T-test at a significant P < 0.05. Comparisons between the cucumber plants of both groups included karyotypes and chromosome shapes, idiograms, and sequencing. The results revealed that, on average, the taller plants came from F1 populations (93.49 cm), followed by mutants of the same cultivar (67.83 cm). The F₁ hybrids showed early flowering (29.00 days) compared with colchicine-treated mutants (33.31 days). However, the number of fruits and fruit weight were higher in the mutant variants (9.39 fruits and 1055.39 g), followed by F₁ populations. The karyotypes of cucumber cultivar Mercy F₁ hybrids and mutants have different chromosomes, especially with the arm size. An idiogram also exhibited differences in chromosome length between the variants of both plant groups, while the primers of trnL-F and trnL-R target sequences were the same with the DNA sequence length. Using mutant cucumber seeds demonstrates a change in phenotypic character to increase fruit production. However, polyploidy did not occur, with genetic alterations measured by the length of chromosome arms. As a result, a future study with increased concentrations of colchicine is imperative to obtain significant chromosomal mutations.

Keywords: Cucumber (Cucumis sativus L.), F₁ hybrids, colchicine mutants, growth traits, phenotypic characteristics, genetic diversity, chromosomes

Key findings: The number of fruits and fruit weight were higher in the mutant populations, while the Brix values and plant height were better in F₁ hybrids compared with the mutants in cucumber (Cucumis sativus L.). The varied karyotypes between F₁ and mutant populations with short-arm (p) and long-arm (q) size indicate significant differences in the number of genes. The variation in chromosome arm length phenotypically causes changes in the morphological characters. Therefore, it is necessary to enhance the colchicine concentration and immersion time to obtain polyploidy.

Drought is among the severe abiotic stresses that reduces crop yield. It greatly affects the growth and development at both vegetative and reproductive stages and the yield processes of crops. Maize is the third most important and widely distributed crop, suffering from drought stress, resulting in final kernel yield losses. The conduct of a screening experiment selected drought-sensitive and drought-tolerant maize accessions against water stress applied via calculating field capacity. This experiment used two treatments, T₀ and T₁ (T₀ with 100% field capacity and T₁ with 50% field capacity), in a completely randomized design (CRD) with a factorial arrangement and two replications at the wirehouse, Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan. Recording data on seedling traits ensued. Drought-tolerant and drought-sensitive accessions’ selection resulted from principal component analysis, with a conclusion that the accessions H45C × H6B, H21 × H2B, H17 × H16, H23 × H21, H17 × H16A were drought tolerant, while H20 × H7C, H47A × H6C, and H9 × H21 were drought sensitive. This research will provide information in the future for comparing drought-sensitive and drought-tolerant accessions and help identify drought-tolerant maize accessions benefitting future breeding programs.

Keywords: Drought stress, screening, production, genetic variability, selection, principle component analysis, drought tolerant, drought-sensitive

Key findings: Among 50 accessions screened against drought stress, the accessions H45C × H6B, H21 × H2B, H17 × H16, H23 × H21, and H17 × H16A were drought tolerant, while H20 × H7C, H47A × H6C, and H9 × H21 were drought sensitive. These accessions will benefit future breeding programs for comparing drought-sensitive and drought-tolerant accessions to develop drought-tolerant maize accessions.

Adding organic matter to soil proved an efficient strategy for restoring soil fertility and improving crop dry matter – an indicator of yield potential. In this regard, evaluating the sources of organic matter (OM) (control, poultry manure [PM], farmyard manure [FYM], compost, and mungbean residues [MR]) to provide 120 kg N ha^-1 and effective microbes (EM) (0, 100, 200, and 300 L ton^-1 of OM) as 2% solution proceeded in field conditions during 2017–2019. The sowing of wheat seeds (cv. Pirsabak 2015) at 120 kg ha^-1 took place in the field using RCB design with four replications. Results showed that PM/FYM had delayed the phenology and improved the biomass-related parameters, dry matter (DM) accumulation, and crop growth rate (CGR) more than compost and MR. However, the results were more pronounced when applied with 300 L EM ton^-1 of OM from the PM. The maximum DM (55%) accumulation in plant parts occurred beyond 100 days after sowing (DAS). A marked increase in DM and CGR beyond 60 DAS and a reduction in CGR beyond 120 DAS appeared irrespective of treatments. In the case of EM, the 300 L ton^-1 revealed superior in terms of growth, DM accumulation, CGR, and delayed phenology. Structural equation modeling suggested that DM production gained a direct effect from crop phenology (46.1%) and crop stand (30.4%) but no indirect effect from crop growth (24.8%). In conclusion, the 300 L EM ton^-1 of OM applied to PM or FYM had improved the crop stand, development, and DM production in wheat.

Keywords: Wheat, structural equation model, poultry/farmyard manure, compost, mungbean residues, effective microbes, crop growth

Key findings: Phenology was delayed using PM and FYM, thereby increasing the plant growth and dry matter accumulation over compost and MR. Improved DM and CGR resulted from PM, FYM, and MR with higher levels of 300 L ton^-1 of OM versus compost with a lower level of EM (100 L ton^-1 of OM). More than 50% of dry matter accumulation occurs after spikes emergence. DM production was directly affected by crop phenology (46.1%) and crop stand (30.4%) but indirectly affected by crop growth (24.8%).

The present study, comprising an evaluation of cotton amphidiploid hybrids and their families for yield and fiber quality traits, commenced from 2007 to 2022 at the Chirchik State Pedagogical University, Tashkent, Uzbekistan. The amphidiploid hybrids’ creation was through interspecific hybridization of Gossypium hirsutum subsp. euhirsutum cultivar Kelajak × F₁ (G. arboreum subsp. perenne × G. arboreum subsp. obtusifolium var. indicum) and experimental polyploidy, with genetically enriched new genotypes obtained. According to genetic variability, a considerable variation showed based on F₁–F₆ populations belonging to various clusters for the traits boll weight (2.3–6.21 g), 1000-seed weight (67.3–125.529 g), fiber length (24.9–34.4125 mm), fiber yield (31.4%–40.26%), and fiber index (6.3–7.5875 g). Furthermore, among the F₆ G. hirsutum subsp. euhirsutum cultivar Kelajak × F₁ (G. arboreum subsp. perenne × G. arboreum subsp. obtusifolium var. indicum) combination families, the promising genotypes selected gave the highest trait values for boll weight (6.6 ± 0.13 g – Family- 41), 1000-seed weight (125.8 ± 3.48 g – Family-59), fiber yield (40.3% ± 0.65% – Family-59), fiber index (8.5 ± 0.23 g – Family-59), and fiber length (34.5 ± 0.16 mm – Family-8). Genotype evaluation using cluster analysis allows the prediction of cotton families with a better combination of traits. Introgressive hybrids created based on the early maturing families, viz., Family-5, Family-8, Family- 13, Family-14, Family-41, and Family-59, with high yields and fiber indices attained inclusion in the Cotton Gene Pool, Uzbekistan (Certificate of the Academy of Sciences of the Republic of Uzbekistan No. 4/1255-2635 dated November 26, 2020). The promising families selected based on their best performance included F₅ (G. hirsutum L. × F₁ [G. arboreum L. × G. arboreum L.], Family-5, Family-8, Family-13, Family-14, and Family-59) and F₆ (G. hirsutum L. × F₁ [G. arboreum L. × G. arboreum L.], Family-5, Family-13, and Family-59), with the said cotton gene pool as valuable recombinants benefiting future breeding programs.

Keywords: G. hirsutum subsp. euhirsutum, G. arboreum subsp. perenne, G. arboreum subsp. obtusifolium, amphidiploid hybrids, F₁–F₆ populations, boll weight, 1000-seed weight, fiber length, fiber yield

Key findings: Results revealed considerable variations were among the primary cotton sources and interspecific amphidiploid F₁–F₆ populations for yield and fiber quality traits. Based on various economic traits, the cotton genotypes showed a relationship with different clusters.