Total Marketable Yield Research Articles

Development and Evaluation of IPM modules against fruit borer (Helicoverpa Armigera) infesting tomato crop

Field studies on the “Development and evaluation of different management schedules against fruit borer, Helicoverpa armigera infesting tomato crop" were carried at farmer’s field, village Surajgarh, Jhajjar, Haryana. The observations on infestation of fruit borer in tomato fruits at the time of each picking, %reduction of the fruit borer infestation, total marketable yield in different schedules over control and benefit cost ratio were calculated. The maximum larval reduction over control was observed in S6 i.e. spray of fenvalerate 20 EC @ 188 ml/ha (79.91%) followed by spray of nimbecidine 300 ppm @ 2.5 l/ha (79.04). On number basis, highest fruit damage reduction over control was observed in S6 (50.23%) followed by S5 (43.83%) and lowest (21.72%) in S4 i.e. African yellow marigold + yellow sticky trap + Trichogramma chilonis Ishi @ 50000 parasitised eggs/ha (2 releases at 4 days interval). On weight basis, %fruit damage reduction over control was maximum in S6 (57.47%) followed by S5 (53.10%) and minimum in S4 (25.06%). The highest benefit cost ratio (22.81) was recorded in S6 due to lowest cost of plant protection (Rs.3628.34/ha) and highest increased yield over control (72 q/ha). Although schedule S4 was next to S6 in term of total cost of plant protection but showed lowest benefit cost ratio (3.46) due to minimum increased yield over control (20 q/ha) among all the management schedules. Benefit cost ratio in remaining schedules were 8.97, 5.40, 3.71 and 3.58 in S5, S1, S2 and S3, respectively.

Adaptability of Phytophthora capsici Resistant Bell Pepper Cultivars in Southern Georgia

Phytophthora capsici (PCap), which causes Phytophthora root rot, is the most destructive soilborne pathogen for bell pepper (Capsicum annuum L.) production in Georgia, USA. Extensive host range, persistence of inoculum in the soil, and lack of effective chemical control methods make this disease particularly difficult to manage. Resistant cultivars offer a practical solution to manage PCap in affected bell pepper fields. However, most commercial cultivars resistant to PCap are predominantly grown in the northeastern United States. This research aimed to screen commercial bell pepper cultivars for resistance to PCap, marketable yield, fruit size distribution, and overall adaptability for production within the largest growing areas in southern Georgia. Field trials were conducted during Spring 2022 and 2023 in commercial growers’ fields with a known history of PCap infestation to evaluate PCap-resistant bell pepper cultivars across four trials conducted in the three counties (Colquitt, Echols, and Lowndes) responsible for ∼78% of bell pepper production in Georgia. Eleven cultivars were evaluated: nine that claimed PCap resistance and two widely grown PCap susceptible cultivars included for comparison. Phytophthora root rot incidence was very low in these research trials. However, there were significant differences in total yields, marketable yields, fruit size, and unmarketable yields. On the basis of marketable yields for jumbo, extra large, and large-sized fruit, we recommend the PCap-resistant cultivars PS 0994-1819, Paladin, and Mercer for fresh market bell pepper growers. Furthermore, ‘Revolution’ is recommended for processor growers due to higher jumbo-sized fruit yields and lower quality and higher pancaking for the spring season in southern Georgia, USA. Newer cultivars Tarpon and Nitro have a more desirable disease-resistance package; however, ‘Nitro’ had small-sized fruit, and ‘Tarpon’ tended to have lower total yields than current commercial standards.

Adaptability and Yield Performance of Introduced Tomato Lines under Greenhouse and Open Field Conditions in Honduras

In Honduras, tomato (Solanum lycopersicum L.) is an economically important crop for farmers because of its high domestic consumption, year-round production, and high export potential. However, tomato production faces challenges such as diseases and pests and is confounded by climate change, all of which reduce productivity and quality. Evaluating the adaptation of tomato cultivars is critical to ensuring the long-term sustainability and resilience of the horticulture sector in the region. The objective of this study was to identify tomato lines with adaptability, high yield, pest, and disease resistance under greenhouse and open field production conditions for the Honduran market. Ten tomato lines and two commercial hybrids were evaluated between Feb and Jul 2022 in San Antonio de Oriente, Francisco Morazán, Honduras. Desirable traits related to vegetative growth, productivity, fruit quality, and resistance to insect pests and diseases were measured. Seven lines were highly adapted and had high vegetative growth. The tomato lines were not significantly different in terms of tomato yellow leaf curl disease and late blight disease index; however, the fruit borer susceptibility varied, with AVTO1908 being the most susceptible. The highest performing line was AVTO1903, which had the greatest total marketable yield in both the open field (101.3 t⋅ha−1) and greenhouse (62.1 t⋅ha−1). Additionally, AVTO1903 and AVTO1915 had good quality traits (roundness index, total soluble solids, and dry matter), thus demonstrating their potential for sustainable and high-yielding cultivation in Honduras. The growth and productivity of the tomato lines were highly influenced by the environment. This work highlights the advantages of introducing exotic cultivars to combat the effects of climate change and ensure sustained production; however, further research is needed to ensure that local farmer and consumer demands are met.

A complex biostimulant based on plant flavonoids enhances potato growth and commercial yields

IntroductionPotatoes are one of the world’s most important agricultural crops, with potential for making a major contribution to global food security. This study shows how a biostimulant derived from a plant extract can improve potato crop yield and global food supply. Successful potato production currently requires significant levels of inputs including fertiliser, pesticides and irrigation, however non-microbial plant biostimulants or mixtures of biostimulants with synergistic actions, have the capacity to reduce inputs and improve the sustainability of intensive agriculture.MethodsA complex biostimulant containing a number of flavonoids including protocatechuic acid, quercetin, chlorogenic acid, coumaroyl quinic acid and gentistic acid was tested against three potato varieties for its efficacy in improving plant growth characteristics and tuber production in controlled and field environments.ResultsIn containers, complex biostimulant treatment enhanced photosynthetic ability, with elevated levels of chlorophyll, higher specific leaf areas and significantly larger leaf assimilation areas. Treatment also significantly increased tuber yield by an average of 33% in tuber weight across three potato varieties and shifted tuber production toward larger sized tubers. The biostimulant derived from flavonoids was also assessed in 6 commercial potato crops and consistently increased total yield (average 5.2%) and marketable yield, representing an increase in margins of UK£700 per hectare across the 6 crops. Similar increases in yield were seen when comparing chitted and unchitted seed potatoes and both types of seed responded positively to biostimulant application. Biostimulant treatment had no significant effects on tuber specific gravity, dry matter percentage and starch content, except at one location where these quality characteristics were higher in the control plants.ConclusionThe flavonoid based complex biostimulant produced significant effects on potato yield and quality in both container experiments and in field trials indicating its potential for contributing to sustainable potato production.

Association and Path Coefficient Analysis Studies in Potato (Solanum tuberosum L.) Genotypes at Adet, Northwestern Ethiopia

The experiment was conducted during main rain fall season from June to October, 2018 in Adet, Ethiopia with the objective of estimating the correlation and identifying the direct and indirect effect of yield contributing traits on potato crop. 36 potato genotypes were evaluated in simple lattice design in two replications. The analysis of variance revealed that highly significant (p<0.001) difference among potato genotypes for all traits except average stem number. Total tuber yield was positively correlated with days to maturity, plant height, average stem number, marketable, unmarketable, total tuber number and marketable yield while it was negatively correlated with late blight severity percentage at both phenotypic and genotypic level. High correlation was observed between total tuber yield and marketable tuber yield (rp=0.982 and rg=0.986) followed by total tuber number (rp=0.735 and rg=0.789), and marketable tuber number (rp=0.700 and rg=0.737). Days to flowering, days to maturity, average stem number, marketable and unmarketable tuber number, starch content percentage, average tuber weight, and unmarketable tuber yield had positive direct effect on the total tuber yield at both genotypic and phenotypic level. Highly direct effect on total tuber yield was observed by marketable and unmarketable tuber number (3.65 and 1.17 respectively) and average tuber weight (0.56). Therefore, traits with significant positive correlated and direct effect on total tuber yield such as days to maturity stem number, marketable tuber number, marketable tuber yield and average tuber weight should be considered in selection criteria for enhancing tuber yield in potato.

Modulation of cherry tomato performances in response to molybdenum biofortification and arbuscular mycorrhizal fungi in a soilless system

Molybdenum (Mo) is a crucial microelement for both, humans and plants. The use of agronomic biofortification techniques can be an alternative method to enhance Mo content in vegetables. Concomitantly, arbuscular mycorrhizal fungi (AMF) application is a valuable strategy to enhance plant performances and overcome plant abiotic distresses such as microelement overdose. The aim of this research was to estimate the direct and/or indirect effects of Mo supply at four doses [0.0, 0.5 (standard dose), 2.0 or 4.0 μmol L−1], alone or combined with AMF inoculation, on plant performances. In particular, plant height and first flower truss emission, productive features (total yield, marketable yield and average marketable fruit weight) and fruit qualitative characteristics (fruit dry matter, soluble solids content, titratable acidity, ascorbic acid, lycopene, polyphenol, nitrogen, copper, iron and molybdenum) of an established cherry tomato genotype cultivated in soilless conditions were investigated. Moreover, proline and malondialdehyde concentrations, as well as Mo hazard quotient (HQ) in response to experimental treatments were determined. A split-plot randomized experimental block design with Mo dosages as plots and +AMF or -AMF as sub-plots was adopted. Data revealed that AMF inoculation enhanced marketable yield (+50.0 %), as well as some qualitative traits, such as fruit soluble solids content (SSC) (+9.9 %), ascorbic acid (+7.3 %), polyphenols (+2.3 %), and lycopene (+2.5 %). Molybdenum application significantly increased SSC, polyphenols, fruit Mo concentration (+29.0 % and +100.0 % in plants biofortified with 2.0 and 4.0 μmol Mo L−1 compared to those fertigated with the standard dose, respectively) and proline, whereas it decreased N (−25.0 % and −41.6 % in plants biofortified with 2.0 and 4.0 μmol Mo L−1 compared to those fertigated with the standard dose, respectively). Interestingly, the application of AMF mitigated the detrimental effect of high Mo dosages (2.0 or 4.0 μmol L−1). A pronounced advance in terms of plant height 45 DAT, fruit lycopene concentration and fruit Fe, Cu and Mo concentrations was observed when AMF treatment and Mo dosages (2.0 or 4.0 μmol Mo L−1) were combined. Plants inoculated or not with AMF showed an improvement in the hazard quotient (HQ) in reaction to Mo application. However, the HQ - for a consumption of 200 g day−1 of biofortified cherry tomato - remained within the safety level for human consumption. This study suggests that Mo-implementation (at 2.0 or 4.0 μmol L−1) combined with AMF inoculation could represent a viable cultivation protocol to enhance yield, produce premium quality tomato fruits and, concomitantly, improve Mo dose in human diet. In the light of our findings, further studies on the interaction between AMF and microelements in other vegetable crops are recommended.

Rejuvenating potato growth and yield in challenging semiarid and saline sandy Cholistan: harnessing PGPB-coated N and P application strategies

BackgroundPotato serves as a major non-cereal food crop and income source for small-scale growers in Punjab, Pakistan. Unfortunately, improper fertilization practices have led to low crop yields, worsened by challenging environmental conditions and poor groundwater quality in the Cholistan region. To address this, we conducted an experiment to assess the impact of two fertilizer application approaches on potato cv. Barna using plant growth-promoting bacteria (PGPB) coated biofertilizers. The first approach, termed conventional fertilizer application (CFA), involved four split applications of PGPB-coated fertilizers at a rate of 100:75 kg acre–1 (N and P). The second, modified fertilizer application (MFA), employed nine split applications at a rate of 80:40 kg acre–1.ResultsThe MFA approach significantly improved various plant attributes compared to the CFA. This included increased plant height (28%), stem number (45%), leaf count (46%), leaf area index (36%), leaf thickness (three-folds), chlorophyll content (53%), quantum yield of photosystem II (45%), photosynthetically active radiations (56%), electrochromic shift (5.6%), proton flux (24.6%), proton conductivity (71%), linear electron flow (72%), photosynthetic rate (35%), water use efficiency (76%), and substomatal CO2 (two-folds), and lowered non-photochemical quenching (56%), non-regulatory energy dissipation (33%), transpiration rate (59%), and stomatal conductance (70%). Additionally, the MFA approach resulted in higher tuber production per plant (21%), average tuber weight (21.9%), tuber diameter (24.5%), total tuber yield (29.1%), marketable yield (22.7%), seed-grade yield (9%), specific gravity (9.6%), and soluble solids (7.1%). It also reduced undesirable factors like goli and downgrade yields by 57.6% and 98.8%, respectively. Furthermore, plants under the MFA approach exhibited enhanced nitrogen (27.8%) and phosphorus uptake (40.6%), with improved N (26.1%) and P uptake efficiency (43.7%) compared to the CFA approach.ConclusionThe use of PGPB-coated N and P fertilizers with a higher number of splits at a lower rate significantly boosts potato production in the alkaline sandy soils of Cholistan.

Spacing and Tomatotone Influence on Yield of Rain Fed Tomato (Solanum lycopersicum L.) in Sudan Savanna of Nigeria

Spacing and Tomatotone Influence on Yield of Rain Fed Tomato (Solanum lycopersicum L.) in Sudan Savanna of Nigeria

Growth and Yield of Summer Squash (Cucurbita pepo L.) as Influenced by Different Coloured Plastic Mulches in the Tarai Region of Uttarakhand

Summer squash is a short-duration vegetable crop with off-season nature and high economic returns per unit area. However, the early crop growth season encounters a number of abiotic stresses like low temperature and frost, which adversely affect the marketable yield and quality of the fruits. This dependency on natural factors restricts the scope of its profitable cultivation, thereby making it necessary to bring more area under protected cultivation. Coloured plastic mulches are an important component of protected cultivation, which are designed to modify the microclimate at the plant and soil levels so as to increase crop production and productivity, as well as quality of the produce, to meet the demands of the consumers. Keeping these considerations in view, the present field investigation was conducted at the Vegetable Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar (Uttarakhand) during the rabi season of 2019-20 to study the effect of different coloured plastic mulches on the growth and yield of summer squash (Cucurbita pepo L.). The experiment comprised nine treatments (bi-coloured plastic mulches) replicated thrice in a randomised block design. Results revealed that use of different coloured plastic films significantly influenced the growth and yield parameters of summer squash. Red coloured plastic mulch (V1) recorded the maximum values for fruit length (30.78 cm), fruit yield plant-1 (1975.8 g), fruit yield plot-1 (39.51 kg) and total marketable fruit yield (365.52 q ha-1), while biodegradable film of silver-black colour (V7) and black plastic mulch (V4) recorded the maximum plant height (cm) and plant spread (cm), respectively. The maximum diameter of the fruit (110.13 mm) was recorded under black coloured plastic mulch. Considering the prevalent climatic conditions of the tarai region of Uttarakhand, red coloured plastic mulch can be recommended for commercial cultivation of summer squash for obtaining higher fruit yields.

Impact of training methods and biostimulant applications on sweet pepper (Capsicum annuum) yield and nutritional values: Under greenhouse condition

Pepper (Capsicum annuum L.) is an important agricultural crop because of the nutritional value of the fruit and its economic importance. Various techniques have been practiced to enhance pepper's productivity and nutritional value. Therefore, this study was conducted to determine the impact of different training methods and biostimulant applications on sweet pepper plants' growth, yield, and chemical composition under greenhouse conditions. For the training method, unpruned plants were compared with one stem and two stem plants. Unpruned plants had the fruit number of 33.98, fruit weight of 2.18 kg·plant−1, and total marketable yield of 1 090.0 kg·hm−2. One stem plant gave the best average fruit weight of 86.63 g, vitamin C content of 13.66 mg·kg−1 FW, and TSS content of 7.21%. However, two stem plants had the highest fruit setting of 62.41%, carotenoid content of 0.14 mg·kg−1 FW, and fruit chlorophyll content of 3.57 mg·kg−1 FW. For biostimulant applications, control plants were compared with the Disper Root (DR) and Disper Vital (DV). DR application significantly increased total sugar, carotenoid, fruit chlorophyll, and TSS contents compared to the control and DV applications. While, applying DV increased fruit setting, plant fruit number, weight, and total marketable yield. In addition, integrating one stem plant with the DR application improved fiber, vitamin C, and TSS contents significantly. Two stem plants, and the DV application improved fruit setting and carotenoid content. Thus, one and two stem training methods integrated with the DR and DV biostimulant applications could be considered for developing agricultural practices to obtain commercial yield and improve the nutrition values of sweet peppers, as unpruned plants without biostimulant applications have a negative impact.

Correlation and Path Analysis for Agronomic and Processing Quality Traits of Potato (<i>Solanum tuberosum</i> L.) at Holetta, Central Ethiopia

Potato is the third most important food crop in terms of consumption in the world after rice and wheat. It is a nutrient-rich vegetable with just a small amount of fat and contains 16% carbohydrates, 2% proteins, 1% minerals, and 0.6% dietary fiber. The literature on path and correlation analysis and its application as a potato breeding tool is limited in comparison to its significance for processing purpose and the knowledge it adds for upcoming breeding work. The objective of this study was to determine the relation among tuber yield and processing quality traits of potato using correlation and path coefficient analysis. This experiment was conducted at Holetta Agricultural research Centre, Ethiopia during the main crop season of 2017. The experiment was laid out in randomized complete block design (RCBD) with three replications using 24 potato genotypes. Strong positive and significant correlation were found between total tuber yield and marketable tuber yield (r=0.98) at both genotypic and phenotypic levels. Stronger positive correlations were found between dry matter content and starch content (r= 1) and specific gravity (r=1). Path coefficient analysis of tuber yield and its components shows that dry matter content and marketable tuber yield exerted positive highest direct influence on total tuber yield. Specific gravity of tuber had high positive direct effect on dry matter content. So, to increase the performance of these traits for tuber yield and processing quality traits path analysis can be used. As a conclusion, most of the traits had positive correlations and direct effects with total tuber yield and dry matter content at phenotypic and genotypic levels. Therefore, those traits had practical importance in selection of potato genotypes for high total tuber yield and processing purpose.

Synergistic Influence of Arbuscular mycorrhizal Fungi Inoculation with Nanoparticle Foliar Application Enhances Chili (Capsicum annuum L.) Antioxidant Enzymes, Anatomical Characteristics, and Productivity under Cold-Stress Conditions.

In this study, we aimed to evaluate the effects of Arbuscular mycorrhiza fungus (AMF) inoculation, foliar application of zinc oxide and selenium nanoparticles (ZnO-NPs and Se-NPs), and their combined interactions on the growth and productivity of chili pepper under cold-stress conditions. Two field experiments were successfully conducted during the winter seasons of 2021 and 2022 in an experimental field at the Faculty of Agriculture, Cairo University, Giza, Egypt. The results showed that, under cold stress, the combination of AMF inoculation and ZnO-NPs + Se-NPs as a foliar spray increased the average fruit weight by 92.4% and 98.7%, and the number of fruits by 34.6% and 54.8 compared to control treatment in the 2021 and 2022 seasons, respectively. Additionally, the combination of AMF and a mixture of nanoparticles (ZnO-NPs + Se-NPs) significantly increased the total marketable yield by 95.8% and 94.7% compared to the control, which recorded values of 2.4 and 1.9 kg m-2 in the 2021 and 2022 seasons, respectively. Furthermore, the combination of AMF and a mixture of nanoparticles (ZnO-NPs + Se-NPs) showed the highest total content of ascorbic acid and capsaicin in chili fruits compared to the other treatments. The combination of AMF and a mixture of nanoparticles (ZnO-NPs + Se-NPs) stimulated the accumulation of peroxidase (POD) and nitrogen glutamate dehydrogenase (GDH) while decreasing hydrogen peroxide (H2O2) and lipid peroxidation (MDA) contents. SDS analysis revealed that the application of ZnO-NPs, Se-NPs, AMF + ZnO-NPs, and AMF + ZnO-NPs + Se-NPs induced the emergence of new protein bands and reconstitution of those damaged by cold stress. Regarding histological structure, the combination of AMF inoculation and ZnO-NPs + Se-NPs as a foliar spray showed an enhancement in the thickness of grana thylakoids and increased the number of chloroplasts. Intriguingly, the findings showed that AMF and a mixture of nanoparticles (ZnO-NPs + Se-NPs) could offer guidance for increasing plant development and productivity under cold-stress conditions.

Correlation and Path Coefficient Analysis in Bitter Gourd (Momordica charantia L.) Genotypes

Correlation of various characters with yield is useful and provides criteria for direct selection of component characters. The other genetic parameter commonly used is the path analysis as given by Dewey and Lu, 1959. It critically breaks up different direct and indirect effects which finally add upto the correlation coefficient. The present investigation was undertaken at the Experimental field of Urban Technological Park Habbak, Srinagar, Jammu and Kashmir during kharif-2022. The experiment was laid out in Randomized Block Design with three replications and plant spacing of 2×1 m for thirty genotypes in order to study the association among yield and yield components, their direct and indirect influence on total marketable fruit yield. Observations were recorded on various growth and yield traits and seed traits. Positive and significant correlation was noted for fruit yield ha-1 with number of male flowers plant-1, number of female flowers plant-1, vine length (m), number of fruits, average fruit weight (g), leaf area (cm2), number of seeds fruit-1, seed weight fruit-1 and fruit yield plant-1 both at genotypic and phenotypic levels. Path coefficient analysis disclosed that traits such as number of fruits per plant, vine length (m), number of female flowers, average fruit weight(g) and number of seeds per fruit should be given due importance by selection for breeding of new cultivars as they exhibited the highest direct effects on the fruit yield ha-1.

Cultivo do meloeiro amarelo submetido a diferentes lâminas de irrigação e aplicação do bioestimulante arbolina

ABSTRACT The objective was to evaluate the physiological and biochemical characteristics during flowering, and the total and marketable fruit yield of yellow melon subjected to different irrigation depths and application of the biostimulant Arbolina®. The experimental design was randomized blocks, in a 2×2×5 factorial arrangement of split-split plots, with four replicates. Plots consisted of 2 forms of biostimulant application (fertigation and spraying), subplots consisted of 2 irrigation depths (40% and 100% of crop evapotranspiration - ETc) and sub-subplots consisted of 5 doses of the biostimulant Arbolina® (0; 0.1; 0.2; 0.4; and 0.8 L ha-1). Melon seedlings were transplanted into the soil at a spacing of 2.0 × 0.3 m, with drip irrigation. Basal and topdressing fertilization was performed via fertigation. The variables evaluated were: for total yield and marketable yield, photosynthetic rate, stomatal conductance, internal CO2 concentration, transpiration and leaf temperature, chlorophyll a and b contents, water use efficiency and relative water content. The biostimulant application by spraying had a better effect on the production process of yellow melon plants, promoting better metabolic efficiency in organ-forming cells, including the process of morphological formation and biochemical constitution of the fruits. It is recommended to use of the biostimulant doses of 0.446 and 0.443 L ha-1 combined with the use of 100% of ETc to achieve the highest total and marketable productivity.

Effect of Seed Tuber Size on Growth and Yield of Potato (Solanum Tuberosum L.) Variety Desiree in Dadeldhura

A field study was carried out on potato (Solanum tuberosum L.) variety Desiree to determine the effect of seed tuber size on growth and yield performance in Dadeldhura district in 2023. The experiment was carried out in randomized complete block design (RCBD) using four replications and five treatments. Treatments used were different weighed seed tubers viz.T1:(11-20g),T2:(21-30g), T3:(31-40g), T4:(41-50g), and T5:(51-60g) . The results showed significant effect of the size of seed tubers on the growth and yield of potato. The treatment 51-60g seed tuber proved to be superior in terms of plant height, number of leaves/plant and tuber weight/hill followed by the treatment 31-40g seed tuber. Similarly, at harvest, 31-40g seed tubers yielded maximum number of tubers/hill, number of tuber/m2, total yield, total marketable yield, and average number of stem/hill followed by the treatments 51-60g and 21-30g seed tubers respectively. On the basis of potato tuber grading 21-30g seed tuber yielded bigger sized potato tubers followed by 31-40g and 51-60g respectively. The treatment 31-40g proved to be the best among all the treatments in yielding maximum total yield, total marketable yield and less number of unmarketable tubers. Similarly, the benefit cost ratio obtained from 31-40g seed tuber is significantly higher (3.82) than all other treatments. Hence, 31-40g seed tuber is suggested to farmers for profitable production of potato.

Application of mycorrhizae and rhizobacteria inoculations in the cultivation of processing tomato under water shortage

The effect of mycorrhizal fungi and plant growth promoting rhizobacteria on some physiological properties, yield and soluble solid content (Brix) of ‘Uno Rosso’ F1 processing tomato was studied under water scarcity. Inoculation was performed with mycorrhizal fungi (M) and rhizobacteria preparation (PH) at sowing (M1, PH1) and sowing + planting (M2, PH2). The treated and untreated plants were grown with regular irrigation (RI = ET100%), with deficit irrigation (DI = ET50%) and without irrigation (I0). In drought, the canopy temperature of plants inoculated with arbuscular mycorrhizal fungi (M1, M2) decreased significantly, however, the decrease was small in those treated with the bacterium (PH1, PH2), while the SPAD value of the leaves of plants treated only with Phylazonit increased significantly. On two occasions, inoculations (M2, PH2) significantly increased the total yield and marketable yield, however, under water deficiency, a higher rate of green yield was detected than untreated plants. In dry year using deficit irrigation, the one-time inoculation (M1, PH1) provided a more favorable Brix value, while the double treatments reduced the Brix. In moderate water scarcity, the use of mycorrhizal inoculation (M2) is preferable, while under weak water stress, the use of rhizobacteria inoculation (PH2) is more favorable.

Intermittence in irrigation management and nitrogen optimize yield and water use efficiency in baby lettuce

Aim of the study: To evaluate the influence of irrigation management strategies and nitrogen (N) on baby lettuce growth, yield, and water use efficiency in a protected environment. Area of study: Botucatu, SP, Brazil. Material and methods: The experiments were conducted in two consecutive cycles, and the treatments corresponded to the combination of irrigation management strategies with N doses. Irrigation strategies comprised 3 possibilities: continuous irrigation (Cont); intermittent irrigation with three irrigation pulses at one-hour intervals (Int1); and intermittent irrigation with irrigation depth split and applied at 7:00, 11:00, and 15:00 h (Int2). Two N doses were evaluated, 100 and 130 kg/ha of N, applied in daily fertigation according to the irrigation management strategies. Main results: Intermittent irrigation strategies (Int1 and Int2) promoted the highest vegetative growth, increased leaf water content, and increased total yield (49.55 and 55.30; 46.83 and 49.50 t/ha) and marketable yield (46.77 and 52.44; 45.11 and 47.17 t/ha) in the first and second cycles, respectively, in addition to optimizing water use efficiency. The N dose of 130 kg/ha increased the total yield (51.61 t/ha), marketable yield (48.98 t/ha), and water use efficiencies of total yield (53.60 kg/m³) and marketable yield (50.88 kg/m³) only in the first crop cycle. Research highlights: The use of intermittence in irrigation management proved to be more efficient in obtaining high yields and maximized the efficiency of use of water as a factor of production.

Water-Yield Relationships of Potato in Mediterranean Climatic Conditions

This study was carried out in Isparta University of Applied Sciences, Faculty of Agriculture, Agricultural Research, and Application Farm in 2021 to determine the effect of different irrigation water levels on tuber yield and quality parameters of the Agria potato variety. Drip irrigation method was used in the study and five different irrigation water levels (S1: 120% of the seven-day ETo, S2: 90% of the seven-day ETo, S3: 60% of the seven-day ETo, S4: 30% of the seven-day ETo, S5: No irrigation except germination and emergence) were determined based on the reference evapotranspiration (ETo). Irrigation water (IW) amounts varied between 85.66-639.26 mm and evapotranspiration varied between 296.54-825.15 mm. Different amounts of IW significantly affected the vegetative growth, yield and quality parameters of potato. As irrigation water decreased, total tuber yield and marketable yield declined. Total tuber yield and marketable yield were 46.11 t/ha and 40.59 t/ha, respectively, in S1 treatment where the maximum amount of IW was applied, while they were 12.96 t/ha and 6.37 t/ha, respectively, in S5 treatment where no irrigation was applied. Logarithmic relationships were determined between evapotranspiration and total yield and between the amount of IW and total yield. Water use efficiency was determined between 43.69-55.88 kg/(ha×mm) and irrigation water use efficiency between 32.34-51.86 kg/(ha×mm) and yield response factor (ky) was calculated as 1.19.

Influence of Organic Fertilizer Sources and Application Rates on Onion Production in Georgia, USA

A range of organic fertilizers are available for vegetable crops; however, there is a lack of information regarding the performance and rates of organic fertilizers commonly used in the production of Vidalia onion (Allium cepa). Two commercial organic fertilizers, a mixed source organic fertilizer [MIX (10N–0.9P–6.6K)] and a pelleted poultry litter [PPL (5N–1.8P–2.5K)], were evaluated in two soil types at application rates of 0, 100, 150, 200, 250, and 300 lb/acre nitrogen (N) to determine their impact in the production of Vidalia onions in Georgia, USA, with the objective of determining an optimal fertilizer source and application rate. Field trials were conducted in the 2019–20 and 2020–21 growing seasons in Watkinsville, GA, USA (Cecil series sandy clay loam soil) and Tifton, GA, USA (Tifton series loamy sand soil) on certified organic land. There were significant interactions among location, year, and fertilizer application rate for total marketable yield. In Watkinsville, total marketable yields of onions at different N rates ranged between 1320 and 4565 lb/acre in 2019–20, and between 9951 and 28,749 lb/acre in 2020–21. In Tifton, total marketable yields ranged from 3776 to 9264 lb/acre and 7094 to 14,066 lb/acre in the 2019–20 and 2020–21 seasons, respectively. Aboveground onion N accumulation at harvest was affected by an interaction among location, study year, and fertilizer rate. The largest plant N accumulation was in Watkinsville in 2020–21, ranging from 26 to 50.8 lb/acre N in the 0- and 300-lb/acre N treatments, respectively. In 2020, there were no differences in soil inorganic N at harvest between plots receiving the MIX (9 lb/acre N) or PPL (9.8 lb/acre N) in either location. In 2021, soil inorganic N was greater in plots receiving the MIX fertilizer (14.8 lb/acre N) compared with the PPL fertilizer (11.2 lb/acre N). Yields increased linearly with additional fertilizer; therefore, an optimal application rate for organic fertilizers was not determined.

Impact of Urea Supplements and Cultivars on Yield, Nitrate Accumulation and Some Phytochemical Properties in Lettuce Grown under Greenhouse Conditions

A greenhouse experiment was assayed to study the impact of urea supplements 100, 200, and 300 kg ha-1 and cultivars Nadir, Polaris, and Fajir on the yield, nitrate accumulation and some phytochemical contents in lettuce. The results indicated that all supplemental urea treatments significantly improved stem diameter, chlorophyll intensity in outer leaves, plant yield and total marketable yield. In addition, the urea doses markedly increased nitrate accumulation in leaves, while its accumulation declined at the highest level compared to the other doses. Furthermore, the TPC significantly decreased at the high dose of urea supplement. Additionally, the urea supplement, especially 100 and 300 kg ha-1, notably increased TFC. The Polaris cultivar showed the highest stem diameter, chlorophyll intensity in the inner leaves, dry matter percentage, plant yield, total marketable yield as well as accumulated minimal nitrate in their leaves. Moreover, the highest content of TPC and TFC was obtained by Nadir cultivar. In addition, the Fajir cultivar recorded the highest activity of total antioxidants. Finally, the interaction between Polaris cultivar and 200 kg ha-1 urea maintained a good balance between the yield and its quality. As a result, the findings of this study may help our growers adopt the optimum urea concentrations with lettuce cultivars in their fields under greenhouse circumstances.