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991.
Kosteletzkya virginica, a perennial dicot halophytic species of the Malvaceae, is native to American salt marsh. It was introduced into China as a potential species to improve coastal wetlands and to develop ecologically sound saline agriculture. K. virginica adapts excellently to the tidal-flat habitats in China's east coast, with multiple eco-benefits; in particular, its seed oil could be used to produce biodiesel. The purpose of this study was thus to develop a standardized protocol to induce a high frequency of callus and subsequent plantlet regeneration system for a K. virginica breeding program with the final objective of applying transgenic techniques to improve seed oil yield. The embryonic axes of K. virginica were used as explants for callus induction, shoot induction from the callus and then adventitious root induction from the shoots on nine culture media with different hormone combinations. The best results were achieved on the following media: (1) 93.94% callus induction on MS medium supplemented with 1.0 mg L−1 indole-3-acetic acid (IAA), 0.3 mg L−1 kinetin, 30 g L−1 sucrose and 8 g L−1 agar; (2) 65.83% shoot induction on 1/2MS medium supplemented with 0.1 mg L−1 IAA, 0.5 mg L−1 zeatin, 30 g L−1 sucrose and 8 g L−1 agar; (3) 96.67% rooting on MS medium containing 30 g L−1 sucrose and 8 g L−1 agar. The survival rate of plantlets by organogenic regeneration was 85% after being transplanted into potting soil in flowerpots and placed in the greenhouse. This experiment indicates that we established successful callus induction and plant regeneration protocols for K. virginica. 相似文献
992.
Elisabeth Criscuolo Urbinati Lúcia Helena Vasques José Augusto Senhorini Valéria Leão Souza Flávio Daolio Gonçalves 《Aquaculture Research》2008,39(13):1355-1359
This study compared the larval performance of matrinxã, Brycon amazonicus, after maternal triiodothyronine (T3) injection or egg immersion of T3. In the first experiment, three groups of females (n=4) induced to spawning received pituitary extract (CPE) and a corn oil injection (control), or CPE plus 10 mg or 20 mg kg?1 bw T3 dissolved in corn oil (experimental). Larvae were sampled for body weight and length measurement at hatching (0 h) and 12, 24, 36, 48 and 60 h thereafter. Hatching time, hatching success and abnormal development were monitored. In the second experiment, fertilized eggs from four females were immersed in T3 solutions (0, 0.01, 0.05 and 0.10 mg L?1) and larvae were sampled at hatching (0 h) and 6, 18, 30, 42, 54, 126 and 198 h thereafter. Hatching time was not affected by either means of hormone treatment. Abnormalities decreased as the T3 concentration increased in larvae from T3‐treated broodfish but the number of dead larvae increased proportionally. Larvae from T3‐injected females had higher weight from 24 h after hatching and greater length from hatching, while the weight of larvae produced from T3‐immersed eggs changed at 198 h and length from 126 h of rearing. Both routes of T3 administration affected the early growth of matrinxã but the effect was observed earlier when broodstock females were injected. 相似文献
993.
The genus Psidium includes important fruit crops. However, there are very few studies focusing on its reproductive biology, which limits the establishment of breeding programs. The present work investigated the reproductive biology of Psidium guajava and Psidium cattleianum in terms of compatibility of crossings between these two species aiming at interspecific hybridization because the latter species is an important source of resistance against the nematode Meloidogyne enterolobii. Several types of crosses were performed to understand the reproductive biology of these species, including the compatibility of intra- and interspecific crossings, using assisted in vivo germination of pollen grains on the stigma. In addition, the in vitro germination of both Psidium species was studied at different stages of fruit development to rescue young seeds to improve the chances of obtaining the hybrids. No fruits of 270 pollinations were obtained on guava buds at the pre-anthesis stage, regardless of the source of the pollen grain and the cultivar used as female genotype. Microscopic analyzes demonstrated the germination of pollen grains and pollen tube growth at crosses between guava cv. ‘Pedro Sato’ (P. guajava) and Psidium cattleianum. High germination percentages of Psidium cattleianum seeds were obtained in MS medium without sucrose or containing 15 g/L of this carbohydrate. 相似文献
994.
Bárbhara Joana dos Reis Fatobene Vinícius Teixeira Andrade Giulia Stefania Aloise Maria Bernadete Silvarolla Wallace Gonçalves Oliveiro Guerreiro Filho 《Euphytica》2017,213(8):196
Arabica coffee production is based on highly productive cultivars; however, these cultivars are susceptible to infestation by several biotic agents, including root-knot nematodes. Collections of wild Coffea arabica germplasm represent an important source of genetic variability for resistant cultivar development. In this study, 1046 plants derived from 71 wild coffee trees were evaluated with respect to Meloidogyne paranaensis resistance. In addition to information on plants reactions, we also evaluated the genetic parameters related to resistance. Progenies from the five most promising plants were also evaluated regarding resistance to M. incognita and M. exigua. The yield potential of selected plants was estimated through analysis of data for fruits harvested in 4 different years. Forty-seven plants were considered resistant based on reproduction factor values. The estimated heritability was high for all analyzed variables leading to substantial selection gain, mainly at the progeny mean level. On the basis of heritabilities and genetic correlations, we conclude that selection could be performed based on values of the gall and egg mass index. However, higher genetic gain could be obtained based on nematode count variables. A second experiment confirmed the reactions of the selected five plants to M. paranaensis, and multiple resistance was detected in three of them. The resistant accessions also have yield potential. 相似文献
995.
Elaine Facco Celin Francisco Davi da Silva Nádylla Régis Xavier de Oliveira Rita de Cássia Souza Dias Fernando Antonio Souza de Aragão 《Euphytica》2017,213(5):101
The leafminer Liriomyza sativae (Diptera: Agromyzidae) stands out as the main plant health problem in melon in the Northeast region of Brazil, which is the main region for production and export of the fruit. Genetic resistance of plants is an important strategy in management of this pest. The plant BAGMEL 56-R was selected as a new source of resistance to L. sativae through antibiosis; this resistance is characterized by the death of larvae soon after they begin feeding on the leaf mesophyll; the result is leaf mines that are small and insignificant in terms of yield reduction. Lines with contrasting levels of resistance were obtained from the progenies of this source of resistance through successive self-pollinations, conducted by the pedigree breeding method. Through the segregation pattern of the progenies and the test cross, the genetic nature of resistance was determined; one gene with complete dominance conditions resistance. The name Liriomyza sativae resistance and the symbol Ls are suggested to represent this new gene. In addition, through a non-preference test with lines in contrast for antibiosis and the susceptible hybrid ‘Goldex’, the presence of antixenosis was observed in this source of resistance. Probably, these different types of resistance in the source BAGMEL 56-R are associated with distinct defense mechanisms. Therefore, with this new source, introgression of resistance to L. sativae in elite lines or commercial hybrids of melon is possible. 相似文献
996.
da Silva Paulo Henrique Müller Junqueira Luis Renato de Araujo Marcio José Wilcken Carlos Frederico Moraes Mario Luiz Teixeira de Paula Rinaldo Cesar 《New Forests》2020,51(5):753-763
New Forests - Recently, pest occurrence in forest plantations has been increasing influenced by genotypes and environmental conditions such as climate change, thus impacting production negatively.... 相似文献
997.
Márcia Fernandes Nishiyama Aloisio Henrique Pereira de Souza Hevelyse Munise Celestino dos Santos Aline Kirie Gohara Wilson Massamitu Furuya Lauro Daniel Vargas Mendez 《Journal Of Aquatic Food Product Technology》2013,22(4):471-481
ABSTRACTThis work aimed at increasing the content of calcium and the quality of fatty acid composition of food mixtures developed with by-products from Nile tilapia fed with flaxseed. Mixes using cassava flour and by-products were submitted to analyses of proximate composition, fatty acids and minerals quantification, and sensory assessment. The lipid and protein fractions were higher for the mix containing 30% addition of fish meal. There was an incorporation effect of essential fatty acids in the mix of flours containing fish fed with flaxseed. Calcium had the highest concentration among minerals. Sensory acceptance range was 55–65% for formulations with fish by-products. 相似文献
998.
Carla da Silva Carneiro Eliane Teixeira Mársico Roberta de Oliveira Resende Ribeiro Edgar Francisco Oliveira de Jesus 《Journal Of Aquatic Food Product Technology》2013,22(1):96-102
Total mercury (Hg) levels were determined by cold vapor atomic absorption spectrophotometry (CVAAS) in tissues of two species of carnivorous fishes and in the soft tissue of oysters caught in Sepetiba Bay, Brazil. Hg was distributed unevenly in the organs and tissues of the fish; the mean Hg content was highest in the kidneys (0.048 μg/g wet weight) and lowest in the gills (0.004 μg/g w.w.). Mean Hg levels were higher in the oysters (0.052 μg/g w.w.) than in the fish (0.022 μg/g w.w). The total Hg concentration did not exceed the maximum concentration for food allowed by Brazilian legislation in any of the fish and oyster samples analyzed. Moreover, the Hg concentrations observed were all within the maximum level for fish recommended by the Food and Agriculture Organization (FAO; 0.5 μg/g w.w.). 相似文献
999.
Paulo César Falanghe Carneiro Elaine Correa Swarofsky Daniana Pinotti E. Souza Thiago Mocelin Ramos César Bárbara Baglioli Bernardo Baldisserotto 《Journal of the World Aquaculture Society》2009,40(6):810-817
Salt (NaCl) and gypsum (CaSO4) are used as water additives to mitigate fish stress and improve specimen survival. High stocking densities and the transportation of fish can increase aqueous ammonia, which can, in turn, alter fish cortisol secretion. The objectives of this study were to assess the effects of salt, gypsum, and aqueous ammonia on some stress‐induced physiological responses of jundiá, Rhamdia quelen, juveniles induced by captivity and handling, and to determine the lethal ammonia concentration for this species. Jundiá juveniles were subjected to the following five treatments: water only, water + ammonia (0.4 mg/L), water + NH3 + NaCl (6 g/L), water + NH3 + gypsum (150 mg/L), and water + NH3 + NaCl + gypsum. Blood samples were taken after intervals of 1, 5, 24, and 96 h, and the concentrations of cortisol, glucose, chloride, ammonia, and hematocrit were determined. The NH3 LC50 value after 96 h of exposure (LC50?96h) was measured to be 1.9 mg/L NH3. Either salt or gypsum reduced both cortisol and glucose levels during most of the experimental period, but the combination of both reduced these levels even further. The combined use of NaCl and CaSO4 demonstrates a synergic effect on mitigating stress responses induced by handling and aqueous ammonia in jundiá juveniles. 相似文献
1000.
Patrick Hainfellner Rafael Yutaka Kuradomi Thiago Gonalves de Souza Rafael Tomoda Sato Daniel Guimares Figueiredo‐Ariki Guilherme Antnio de Freitas Luciano Queiroz Wagner C. Valenti Patricia Moraes Valenti Wei Ge Sergio Ricardo Batlouni 《Aquaculture Research》2019,50(11):3382-3391
We evaluated the annual process of oocyte and ovarian development of the planktivorous Amazonian catfish, the mapará (Hypophthalmus marginatus), aiming to support captive reproduction for domestication. A total of 149 females were captured from the Tocantins River at the Tucuruí Dam (3°49'55"S, 49°39'9"W) in 13 sampling events. For each individual, we evaluated ovary histology and plasma steroid concentrations. Two annual reproductive cycles, with similar characteristics, including a long period of rest, a short vitellogenic stage and a well‐defined spawning season from November to March, were described. A 17β‐estradiol (E2) rise and a 17α,20β‐dihydroxy‐4‐pregnen‐3‐one (DHP) peak were associated with vitellogenesis and spawning season, respectively, in the first cycle but not in the second reproductive cycle. In conclusion, the studied species presents a reproductive cycle similar to that of other migratory total spawners; however, unusually for this group of fish, there were three (but not two) batches of vitellogenic oocytes in “in maturation” and “mature” stage ovaries, pointing to the possibility of more than one spawn during the spawning season. 相似文献