The article considers the creation of miniature varieties of nightshade crops. For breeding purposes, wild species and relatives of solanaceous crops were used. We have created miniature varieties of tomato - Emmy, hot pepper - Bouquet, eggplant - Solsis, physalis - Lady, nightshade - Black Karaleva. New varieties can be effectively introduced in the republic and similar regions of the globe.

Local breeding tomato varieties released for cultivation in Armenia in the protected ground conditions have a relatively weak resistance towards disease and stress conditions, despite good taste and quality fruits indicators. This factor, among others, is the reason for the unprofitability of growing tomatoes in greenhouses, which in turn leads to an even greater intensification of production in terms of–pesticides use. The vegetative grafting of vegetable plants can be the problem solution, which helps to increase the disease resistance, yield and improve the fruits quality indicators. The effectiveness of grafted plants depends on the genetic rootstock potential. Collection accessions of tomato and eggplant lines have been evaluated for resistance to fusarium wilt using real-time PCR diagnostics. A preliminary phytosanitary assessment of collection accessions has made it possible to recommend the most disease-resistant samples for using as a rootstock for vegetative grafting. The grafted plants assessment according to a complex of agronomic characters has shown the advantage of using eggplant rootstocks comparing with tomato rootstocks.

The purpose of this work is to study and identify the optimal method of sowing and plant feeding surface in seed-production of melon crop, providing a high yield of healthy varietal seeds with a low self-cost. The experiments were carried out in 2018–2020. on the experimental fields of the Scientific Center of Vegetable and Industrial Crops of the Ministry of Economy of the Republic of Armenia. The influence of the sowing scheme 200+80/2×60, 200+80/2×80 and 200+80/2×100 cm on phenological and quality indicators, fruit and seed productivity, average fruit weight, and resistance to diseases was studied. The study object was mid-early ripening melon variety Arpi, which is distinguished by high productivity and taste quality. The control was the sowing scheme 200+80/2×80 cm, which is generally accepted in the agricultural technology of melon cultivation in the Ararat valley. It was found that in case of low-density planting of plants (1.4 m2), the weight of one fruit is the heaviest (4.0 kg), but the productivity of the fruits is reduced by 11.6% in comparison with the control, and in case of high-density planting by 19.3%. Meanwhile, as the feeding area of one plant increases, in relation to the total yield the marketable yield increases, respectively 92.3%; 94.1% and 95.3%. The results of the experiments allow us to state the fact that high density of the seed producing field (feeding area 0.84 m2) contributes to an increase of seed yield by 27.3% compared to the control, to some extent reducing the self cost of seeds, however significant changes in quality indicators of the Arpi variety were not found. In its turn, early diagnosis of diseases based on the modern PCR method allows to take protective measures in time and accordingly contributes to the production of healthy seeds.

The aim of the present study was to determine the effect of the Indian mycorrhizal preparation Mykonet (Mn) of Endo type on agronomical and economic indicators of the hot and sweet pepper production. The study was conducted with two sweet (Zmrukht and Nush-55) and two hot varieties of pepper (Kon and Punj). The experiments were carried out according to the block randomization method. It has been shown that Mn improves the biological and economic characteristics of sweet and hot peppers, depending on the treatment duration and variety. The most effective was 2 h treatment. The dry matter content was increased slightly, but increased for sugars and ascorbic acid. The best effect was obtained for Zmrukht. Given that Mn has improved the agronomical and economic characteristics of sweet and hot peppers, it can be recommended for pepper production.

Research has been conducted on the effect of the Mycosoil drug on economically valuable traits of tomato of Anahit-351 and Lia varieties, as well as pepper of Hayk and Loshtak varieties. After seed treatment with the Mycosoil drug, seed germination of tomatoes increased by 1.9–2.9%, and of peppers by 4.2–4.4%. Mycosoil contributed to an increase in germination energy: for Anahit-351 tomato variety by 4.3%, and for Lia variety by 6.6%. The germination energy of Hayk and Loshtak pepper varieties increased, respectively, by 1.6–2.5%. For all tomato varieties, the yield gain varied from 9.2 to 9.6%, and for Loshtak pepper variety – 7.5 %. An increase in fruit mass was observed in tomatoes: within 20.6–23.1 g, and in peppers – 5.4–11.1 g. Both the number of seeds formed in one fruit and the mass of 1000 seeds increased. The increase in the number of seeds for tomato varieties ranged between 3.8–4.8 seeds, for pepper – 3.3–7.9 seeds per fruit, and the mass of 1000 seeds increased in the range of 0.5–0.6 g for tomato and 0.3–0.6 g for pepper. When studying the effect of Mycosoil on seedlings in tomato of Anahit and Lia varieties in the variant of Fusarium + Mycosoil, the FAM signal showed values of 20.05–25.40 and it was lower than with control + Fusarium (35.61–38.74).