تراکم بوته مطلوب گوجه‌فرنگی گلخانه‌ای در سیستم کشت بدون خاک در استان گلستان

گوجه‌فرنگی (.solanum lycopersicum l) یک گیاه مهم تجاری و غذایی است. عوامل متعددی بر رشد و نمو گوجه‌فرنگی در گلخانه تاثیرگذارند، که یکی از آن‌ها تراکم کاشت مناسب است. بررسی و معرفی بهترین تراکم بوته در سیستم آب‌کشت، می‌تواند اثر چشم‌گیر بر افزایش عملکرد و بهره‌وری تولید داشته باشد. بدین منظور آزمایشی به‌صورت فاکتوریل در قالب طرح کاملاً تصادفی با سه تکرار با دو تیمار رقم (سه رقم دافنیس، ایزمونو و هیراد) و تراکم (در چهار سطح 2، 2/5، 3 و 3/5 بوته در مترمربع) در گلخانه مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی گرگان در سیستم آب‌کشت انجام شد. در این آزمایش، تعداد خوشه در بوته، تعداد گل در خوشه، درصد ریزش گل، تعداد میوه در خوشه، عملکرد کل بوته، عملکرد در مترمربع، تعداد میوه در بوته، تعداد میوه در مترمربع، میانگین وزن تک میوه، قطر میوه، طول میوه، ضخامت فرابر، همزمان‌رسی میوه‌ها، فاصله بین خوشه‌ها، عملکرد بازارپسند، مواد جامد محلول و ph آب ‌میوه اندازه‌گیری شد. بر اساس نتایج مقایسه میانگین، عملکرد در مترمربع در تراکم زیاد بوته (3/5 بوته در مترمربع) در هر سه رقم به‌طور معنی‌داری بیش‌تر از سایر تیمارها بود. به‌طوری‌که با افزایش تراکم از 3 به 3/5، از 2/5 به 3/5 و از 2 به 3/5 به‌ترتیب در رقم هیراد 2/4، 28/6 و 43/1 درصد، در رقم دافنیس 6/8، 21/7، 23/4 درصد و در رقم ایزمونو 22/7، 35 و 51 درصد افزایش عملکرد در مترمربع مشاهده شد. نتایج نشان داد با افزایش تراکم بوته در مترمربع درصد ریزش گل در بوته‌ها به‌طور معنی‌داری کاهش یافت. بیش‌ترین مقدار مواد جامد محلول در یک رقم (هیراد) در تراکم بیش‌تر مشاهده شد و در دو رقم دیگر تحت تاثیر تراکم قرار نگرفت. ph آب میوه در دو رقم دافنیس و ایزمونو در تراکم 3/5 بوته در مترمربع به‌طور معنی‌داری کم‌تر از سایر تیمارها بود، ولی در رقم هیراد تفاوتی در این صفت بین تراکم‌های مختلف مشاهده نشد. بر اساس نتایج این پژوهش پیشنهاد می‌شود تراکم کشت گوجه‌فرنگی گلخانه‌ای در سیستم آب‌کشت در استان گلستان می‌تواند تا 3/5 بوته در مترمربع افزایش یابد. 

optimum plant density of greenhouse tomato grown in a soilless system in golestan province

abstracttomato (solanum lycopersicum l.) is an important commercial food plant. several factors affect the growth of tomatoes in the greenhouse, and one of them is proper planting density. investigating and suggesting the best density in hydroponic cultivation can have a significant effect on production efficiency. therefore, a factorial experiment was conducted in the hydroponic cultivation system based on completely randomized design with three replications and two treatment of cultivar (dafnis, izmono and hirad) and density (at four density levels of 2, 2.5, 3 and 3.5 plants per m2) in the greenhouse of gorgan agricultural and natural resources research and education center. characteristics of number of clusters per plant, number of flowers per cluster, percent of blossom drop, number of fruits per cluster, fruit yield per plant and per m2, number of fruits per plant, number of fruits per m2, average fruit weight, fruit diameter, fruit length, pericarp thickness, uniform fruit ripening, distance between clusters, marketable yield, total soluble solids and ph of fruit juice were measured. according to the mean comparisons, the average yield per m2 at high plant density (3.5 plants per m2) in all three cultivars was significantly higher than others. with the increase of density from 3 to 3.5, from 2.5 to 3.5 and from 2 to 3.5 plants per m2, respectively, relative increases in yield per m2 of 2.4%, 28.6% and 43.1% in hirad, 6.8%, 21.75%, 23.4% in dafnis and 22.7%, 35% and 51% in izmono were observed. with the increase of plant density, the percentage of blossom drop of plants decreased significantly. the highest total soluble solids content of one cultivar (hirad) was observed in the highest density and two other cultivars were not affected. the ph of fruit juice of dafnis and izmono at a density of 3.5 plants per m2 was significantly lower than other treatments, but there was no difference for this trait in hirad cultivar between different densities. the results of this study suggest to increase the density of tomato in hydroponic greenhouse in golestan province up to 3.5 plants per m2.background and objective: contrary to popular belief, greenhouses are not completely isolated from the outside environment. the condition inside the greenhouse tend to change constantly under the influence of external weather changes (omid et al., 2004). one of the management techniques in increasing the quantity and quality of fruit is the use of proper plant density (kumar singh et al., 2021). due to the high cost of crop production in greenhouses and in order to achieve the maximum production potential of the plant, it is necessary to carry out more precise agricultural operations such as optimizing the density of plants. investigating and introducing the best plant density in hydroponic cultivation can have a significant effect on increasing yield and production efficiency in golestan province greenhouses.methods: a factorial experiment was carried out in the hydroponic cultivation system based on completely randomized design with three replications in the greenhouse of gorgan agricultural and natural resources research and education center. three greenhouse tomato hybrid cultivars including dafnis, izmono and hirad were cultivated at four density levels of 2, 2.5, 3 and 3.5 plants per m2. the following traits were evaluated in this study: fruit yield per plant and per m2, number of fruits per plant and per m2, number of clusters per plant, number of flowers per cluster, percent of blossom drop, number of fruits per cluster, average fruit weight, fruit diameter, fruit length, pericarp thickness, uniform fruit ripening, distance between clusters, marketable yield, total soluble solids and ph of fruit juice.results: the results of analysis of variance showed that fruit yield per plant, fruit yield per m2, number of fruits per plant, number of fruits per m2, average fruit weight, fruit length, number of fruits per cluster, average distance between clusters, percent of blossom drop, uniform fruit ripening, pericarp thickness and ph of fruit juice were affected by the density factor. the results of mean comparisons showed that with the increase of density from 3 to 3.5, from 2.5 to 3.5 and from 2 to 3.5 plants per m2, respectively, relative increases in yield per m2 of 2.4%, 28.6% and 43.1% in hirad, 6.8%, 21.75%, 23.4% in dafnis and 22.7%, 35% and 51% in izmono were observed. correlation analysis of studied traits indicated that the fruit yield per m2 had strong and significant correlation with the number of fruits per plant (r = 0.82**), but it had a negative and significant correlation with the average fruit weight (r = –0.46**).conclusions: according to the results of quantitative and qualitative traits of tomato, the density of 2 to 2.5 plants per m2, which is considered in most hydroponic greenhouses in golestan province, can be increased to 3.5 plants per m2 density.references:1. kumar singh, s., shahi, b.p., singh, b.r., kumar singh, m., singh, s.h and kumar, m., 2021. the effects of plant density on the productivity of tomato hybrids in a newly developed low cost naturally ventilated greenhouse. int. j. plant soil sci. 33(3), 61–72.2. omid, m., shafaii, a., 2004. investigating greenhouse indoor temperature and humidity changes using a computer data collecting system. res. agron. hortic. 64, 67–73. (in persian with english abstract)