The market demand for uniformity and productivity of commercial carrot roots has prioritized hybrid materials over open-pollinated varieties. In this sense, the objective of this work was to estimate the combining ability of carrot genitors for root productivity and resistance to leaf scorch. The experiments were conducted in Gama, DF, in the agricultural years 2012/13 and 2013/14. We evaluated 33 carrot hybrids, originated from crosses between three male-sterile populations, with 11 male-fertile S2 lines, all the genitors being of tropical origin. At 90 days after sowing, the severity of the leaf blight disease was estimated in the plots. At 100 days after sowing, harvesting was performed and root yield characters were evaluated. Analysis of variance and partial diallel analysis were performed for each year and jointly for both years. It was found that additive and non-additive genes are important in the manifestation of root yield and leaf blight resistance traits in carrot hybrids. The male-sterile parents with higher overall combining ability for root productivity are strains LM-649 and LM-650 and, among the male-fertile, strain LM-555-2-2. The best hybrids for root yield and leaf blight resistance are LM-649 × LM-555-11-1, LM-650 × LM-555-7-1 and LM-650 × LM-554-8-1.
Nothofagus pumilio forests constitute the most economically important forest stand in southern Argentina and Chile. Total volume stocking and volumetric yield vary according to site quality, degree of occupation, growth stage and forest history of the stand. The objective of this work was to evaluate the stocking and the productive potential in quantity and quality of products for the sawmilling industry, using three harvesting systems (short logs, long logs and complete shafts) in the protection cut of a N. pumilio forest of site quality III in Tierra del Fuego (Argentina). The trials were conducted in an irregular mature forest with two strata and abundant regeneration (3.0 ha; RDI 93.8–113.4%). Total volumes varied between 726.5 and 850.3 m3∙ha-1, with a volume/basal area ratio of 11.8 to 12.1 m3∙m-2. The harvesting rates obtained were: 45.5% for complete logs, 21.3% for long logs and 22.4% for short logs. A model was used to estimate the timber volume for each system, where full shafts resulted in a significant increase in timber volume. Considering new alternatives in the planning of harvesting in forest management for N. pumilio forests, such as the system of complete shafts, allows obtaining higher harvesting rates, increasing the benefits for the forestry company and minimizing the damage to the forest, due to the shorter distance of the machinery in the forest harvesting.
In order to explore the preliminary effect of 1-MCP application at seedling stage on the growth effect and yield of open field cucumber, this experiment conducted cultivation experiments on three application periods (leaf spraying at one leaf stage, 2 days before planting, spraying after the third harvest), two treatment times (one treatment, two treatment), and two management methods (removing the first and second female flowers, and conventional management). The results showed that in the open field cucumber cultivation experiment, the application of 1-MCP at seedling stage could promote the growth of cucumber, and the T4 treatment was the best, and the second treatment was better than the first treatment; T4 (0.35 mL 1-MCP + treatment 2 days before colonization + after the third harvest + routine management) treatment scheme had the best effect.
With the purpose of identifying the characteristics of variation in fruit size and seed production (potential and efficiency) of Cedrela odorata L. between sites and progenies established in the ejido La Balsa, municipality of Emiliano Zapata, Veracruz, fruits were harvested from 20 trees in February 2013, preserving the identity of each one. Fruit length and width were measured, seed was extracted and developed and aborted seeds were counted to calculate Seed Production Potential (SPP) and Seed Efficiency (SE). The results showed significant differences between sites and between progenies and for fruit length between sites. The mean values found were: 32.52 mm (fruit length), 18.73 mm (fruit width), 39.9 seeds per fruit (SPP) and 57.51% (SE). The seed of this species for its use should be selected taking into account the production characteristics of crops and outstanding individual trees, in addition, due to the current regulatory restrictions on seed collection, the establishment of trials and plantations for germplasm production is a viable option for forest management of the species.
The performance of five cauliflower cultivars in conventional and alternative phytosanitary management—without the use of synthetic pesticides—was evaluated. Two experiments were conducted at Epagri, Ituporanga Experimental Station in February 2018 and 2019. A randomized block design with four repetitions was adopted, with twenty plants of each cultivar as plots. The seedlings were transplanted on millet and mucuna straw at a spacing of 0.5 m × 0.8 m. We evaluated agronomic yield, inflorescence quality, pest damage and plant diseases, especially bacterial and fungal rots. The cauliflower hybrids Vera, Verona and Serena stood out in productivity and quality, being the most indicated for sowing in off-season crops, in the Alto Vale do Itajaí region. The most productive cultivars were less damaged by bacterial diseases and defoliating caterpillars and without interference of whitefly infestation on yield. The results also reveal that it is possible to control pests and diseases with phytosanitary products of lower toxicity, i.e., with lower residues of synthetic pesticides.
In this study, ‘Xinli No. 3’, ‘Shengli rootstock’, ‘Shenli rootstock’ and ‘Shengzhen No. 1’ were used as rootstock, and ‘Jinchun No. 39’ cucumber was used as scion to study the effects of different rootstock on the yield and quality of grafted cucumber, and to select high quality rootstock suitable for cucumber grafting. Different rootstock affected the survival rate, phenology, the height of plant, stem diameter, growth potential, yield and quality of cucumber grafting. Among them, the survival rate of ‘Shenli rootstock’ grafted cucumber is the highest, and the growth of ‘Shengzhen No. 1’ grafted cucumber is relatively the strongest. There was no significant difference in fruit tuber, melon edge, thorn color and pulp crispness between self-rooted seedling (CK) and each rootstock grafting combination. The average yield of ‘Xinli No. 3’ grafted cucumber plot was not significantly different from that of self-rooted seedlings (CK). The length of ‘Shenli rootstock’ and ‘Shengli rootstock’ grafted cucumber was significantly higher than that of self-rooted seedlings (CK), and the length of ‘Shengzhen No. 1’ Grafted Cucumber was significantly higher than that of self-rooted seedlings (CK). The contents of vitamin C and soluble protein of ‘Shengli rootstock’, ‘Shenli rootstock’ and ‘Shengzhen No. 1’ grafted cucumber were significantly higher than those of self-rooted seedlings (CK), and the contents of soluble sugar were lower than those of self-rooted seedlings (CK). Therefore, ‘Shengzhen No. 1’ and ‘Jinchun No. 39’ have strong compatibility with cucumber. As rootstocks, the grafted cucumber plants not only have strong growth potential and high yield, but also significantly increase the content of soluble protein and vitamin C.
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