Desempenho agronômico de alho infectado e de alho livre de vírus com diferentes tamanhos de bulbos e bulbilhos

The objective of this work was to evaluate the growth and production of a garlic clone subjected to either infection or virus-free conditions, according to bulb and clove size classification. The experiment was carried out in a randomized complete block design with four replicates. Treatments consisted of either virus-infected or virus-free cloves, obtained from bulbs of four size classes and from cloves with three sieve diameters. Vegetative characteristics and plant production were assessed. Plants infected by viral complexes showed reduction of emergence (8.4%), plant height (9.8%), and production of marketable bulbs (39.4%), as well as a lower average mass of bulbs and cloves. The virus-free clone produced more bulbs in classes 5 (42–47 mm), 6 (47–56 mm), and 7 (> 56 mm), besides having a lower influence on marketable quality standards as a function of garlic seed size variation. In the infected clone, bulbs from sieve 6 and cloves from sieve 1 (15×25 mm) produced bulbs with the highest market value. Virus-free garlic seed, with bulbs and cloves of medium and large size, produce bulbs of the highest market value, whereas, for the infected garlic, this is possible only with the larger garlic size.O objetivo deste trabalho foi avaliar o crescimento e a produção de um clone de alho submetido a condições de infecção viral e livre de vírus, com base na classificação por tamanho de bulbos e bulbilhos. O delineamento experimental foi em blocos ao acaso, com quatro repetições. Os tratamentos consistiram de bulbilhos infectados com vírus ou não infectados, obtidos de bulbos de quatro classes de tamanho e de bulbilhos com três diâmetros de peneira. Avaliaram-se as características vegetativas e a produção das plantas. As plantas infectadas por complexos virais apresentaram redução na emergência (8,4%), na altura de planta (9,8%) e na produção comercial de bulbos (39,4%), além de menor massa média de bulbos e bulbilhos. O clone livre de vírus teve maior produção de bulbos nas classes 5 (42‒47 mm), 6 (47‒56 mm) e 7 (>56 mm), bem como menor influência no padrão comercial, em razão da variação do tamanho do alho-semente. No clone infectado, os bulbos de classe 6 e os bulbilhos de peneira 1 (15×25) produziram bulbos de maior valor comercial. O alho-semente livre de vírus e com bulbos e bulbilhos de tamanho médio e grande produz bulbos de maior valor comercial, enquanto, para o alho infectado, isto só é possível com o alho de maior tamanho

Breeding new improved clones for strawberry production in Brazil

 Breeding different strawberry genotypes and plant selection in Brazil could result in new cultivars with better environmental adaptations. The aim was to develop and select new F1 strawberry plants with higher potential yields. Twelve hybrid populations were obtained from breeding the cultivars Aromas, Camarosa, Dover, Festival, Oso Grande, Sweet Charlie and Tudla, and 42 F1 hybrids were obtained from each population. An augmented randomized block design was used. Productive traits were measured and heterosis was calculated for all traits. The breedings Dover x Aromas and Camarosa x Aromas both showed 28.6% of their hybrids with a total fruit mass that was higher than that of cv. Aromas, and 9.5 and 14.3% were higher than that of cv. Camarosa, respectively. The breeding of Camarosa x Aromas produced hybrids with high potential yields and a large average fruit mass that reached the commercial standard. Hybrids MCA12-93, MFA12-443 and MCA12-89 showed high potential yields and can be used as parents in strawberry breeding programs.

Genetic divergence among processing tomato hybrids and formation of new segregating populations

ABSTRACT Tomato is the most important vegetable species and has a strong bottleneck effect in its domestication and evolution. In exploring the existing genetic variability in commercial germplasm, germplasm has been proven to be an excellent alternative to obtain inbred lines in order to provide superior new hybrids in the future. In this sense, the objective of this study was to estimate the genetic distance among commercial processing tomato hybrids via agronomical and quality postharvest fruit traits with the aim of suggesting promising crosses for the formation of base populations for tomato breeding. Ten hybrids of processing tomato were evaluated in a complete randomized block design with three replicates. In total, eleven agronomic and postharvest fruit quality traits were evaluated. The genetic distances were estimated between the hybrids using the generalized Mahalanobis () and Gower () distances. The genetic distance among tomato hybrids was determined using a graphic projection of the first two canonical variables. The presence of significant genetic variability among the hybrids (P <0.05) was demonstrated and was sufficient for the selection of the best hybrids before the breeding process. The hybrid Laura stood out for its postharvest characteristics and was the most divergent genotype compared to the others evaluated. The most promising crossings for the formation of segregating populations with superior genetic merit are Kátia x Laura, Vênus x Laura, Fascínio x Laura, AP-533 x Laura, Tinto x Laura, AP-529 x Laura, Supera x Laura, Granadero x Laura, Granadero x AP533, Granadero x Ap529 and Granadero x Kátia

Physiological and isozyme alterations in lettuce seeds under different conditions and storage periods

Abstract: The objective of the study was to determine the physiological and isozyme alterations in lettuce seeds submitted to different conditions and storage periods. We used a completely randomized design with four replications in a factorial arrangement with six lettuce cultivars (Everglades, Babá de Verão, Elisa, Grand Rapids, Hortência and Salinas 88) and four storage periods (30, 60, 90 and 120 days), on three storage rooms (15, 25 and 35 ° C). The physiological quality was evaluated by first and final germination count, emergence, and germination and emergence speed indexes. The isoenzyme expression of catalase (CAT), esterase (EST), alcohol dehydrogenase (ADH) and malate dehydrogenase (MDH) were determined. The physiological quality of lettuce seeds was preserved when stored at 15 ° C room temperature. The high room temperatures associated with higher storage periods cause a reduction in physiological quality and alterations in enzymatic patterns of CAT, EST, ADH and MDH. For seeds stored at 15 ° C, there were no physiological changes. The lettuce cultivars, especially Everglades, have different levels of tolerance to storage and isoenzyme expressions

Overcoming strawberry achene dormancy for improved seedling production in breeding programs

Strawberry achenes present tegument dormancy. This fact, together with the low efficiency of artificial pollination requires a larger number of crossings to ensure the minimum number of achenes used in seedling production in breeding programs. The aim of this study was to test chemical solutions to overcome dormancy in strawberry achenes in order to increase the germination and Germination Speed Index (GSI). The study consisted of two experiments. 1) immersion in H2SO4 (98%), HCl (37%) and NaClO (2%) for 0 (control), 10, 20, 35 and 50 min were evaluated. 2) achenes were immersed in H2SO4 (98%) for 0 (control), 20, 25, 30, 35 and 40 min. A completely randomized design with four replications was used. Germination and GSI were assessed daily for 15 days. Scarification with H2SO4 (98%) for 40 min increased strawberry achene germination to 80% and can be used as a technique to overcome dormancy. Scarification with HCl and NaClO increases germination and the GSI, however, other concentrations and immersion times of those methods should be studied.Los aquenios de la fresa presentan latencia del tegumento. Este hecho, unido a la baja eficiencia de la polinización artificial implica en la realización de un mayor número de cruzamientos para asegurar el número mínimo de aquenios utilizados en la producción de plántulas en programas de mejoramiento. El objetivo de este estudio fue el de probar soluciones químicas para superar la latencia en aquenios de la fresa con el fin de aumentar la germinación y el índice de velocidad de germinación (IVG). Este estudio consistió en dos experimentos. 1) Inmersión en H2SO4 (98%), HCl (37%) y NaClO (2%) para los tiempos de 0 (control), 10, 20, 35 y 50 minutos. 2) los aquenios se sumergieron en H2SO4 (98%) para los tiempos de 0 (control), 20, 25, 30, 35 y 40 minutos. Se utilizó un diseño completamente al azar (DCA) con cuatro repeticiones. La germinación y el IVG fueron evaluados todos los días durante 15 días. La escarificación con H2SO4 (98%) durante 40 min aumenta la germinación de los aquenios de la fresa a 80% y puede ser utilizado como una técnica para superar la latencia. La escarificación con HCl y NaClO aumenta la germinación y el IVG, sin embargo, debe estudiarse junto a otras concentraciones y tiempos de inmersión de esos métodos