RESUMEN
Water deficit is an important climatic problem that can impair agriculture yield and economy. Genetically modified soybean plants containing the AtNCED3 gene were obtained aiming drought-tolerance improvement. The NCED3 gene encodes a 9-cis-epoxycarotenoid dioxygenase (NCED, EC 1.13.11.51), an important enzyme in abscisic acid biosynthesis. ABA activates the expression of drought-responsive genes, in water-deficit conditions, targeting defense mechanisms and enabling plants to survive under low water availability. Results from greenhouse experiments showed that the transgene AtNCED3 and the endogenous genes GmAREB1, GmPP2C, GmSnRK2 and GmAAO3 presented higher expression under water deficit (WD) in the event 2Ha11 than in WT-plants. No significant correlation was observed between the plant materials and WD conditions for growth parameters; however, gas exchange measurements decreased in the GM event, which also showed 80% higher intrinsic water use when compared to WT plants. In crop season 2015/16, event 2Ha11 showed higher total number of pods, higher number of pods with seeds and yield than WT plants. ABA concentration was also higher in GM plants under WD. These results obtained in field screenings suggest that AtNCED3 soybean plants might outperform under drought, reducing economic and yield losses, thus being a good candidate line to be incorporated in the soybean-breeding program to develop drought-tolerant cultivars.
RESUMEN
In a greenhouse experiment, morpho-anatomical and micromorphometrical analyses of two soybean cultivars, MG/BR46 (Conquista) and BR16-tolerant and sensitive to drought, respectively-were used to study their water-deficit-tolerance strategies. Drought treatments were applied at reproductive stages from R2 to R7, where evaluations were conducted at 30 days and 45 days after stress started, respectively. The total length of Conquista plants (shoot + root) was greater than of BR16 plants. Pod dry weight was adversely affected due to the lack of moisture, decreasing productivity even of Conquista plants. Both the cultivars had normal development of root hairs; however, it was observed a decrease in the cortex:central cylinder ratio in BR16 stressed for 30 days, and they also showed similar leaflet thickness and stomata distribution. Differences in drought tolerance observed between the two cultivars seemed to be related to factors other than morphological traits since this species has a short lifecycle.
Análises morfo-anatômicas e micromorfométricas de duas cultivares de soja, MG/BR46 (Conquista) e BR16tolerante e sensível à seca, respectivamente, em experimento conduzido em casa de vegetaçãoforam feitas para estudar as diferentes estratégias de tolerância ao déficit hídrico. Tratamentos de seca foram aplicados no estádio reprodutivo R2 e R7, onde avaliações foram conduzidas em 30 dias e 45 dias após o inicio do estresse, respectivamente. O comprimento total das plantas da cultivar Conquista (parte aérea e raiz) foi maior do que das plantas da cultivar BR16. A massa seca da vagem foi adversamente afetada pelo déficit hídrico, diminuindo a produtividade das plantas da cultivar Conquista. Ambas as cultivares tiveram o desenvolvimento de pêlos radiciais normais e, uma diminuição da razão córtex:cilindro central foi observada em BR16 estressada por 30 dias, além de apresentar uma espessura do folíolo e distribuição dos estômatos normais. Diferenças na tolerância à seca observada entre as duas cultivares devem estar relacionadas também a outros fatores, alm das características morfológicas, já que esta espécie possui um ciclo de vida curto.
RESUMEN
Total RNA isolated from Pectoralis major muscle from PSE (L*24h>53.0, pH<5.8) and non-PSE (44<"L*24h>"53) meats of two phenotypically distinct chicken lines, broiler and layer, was used to investigate the α-ryr and β-ryr gene expression by real-time RT-PCR approach. Mean relative quantification (RQ) values were lower (p<0.05) for β-ryr in PSE chickens from both lines when compared to non-PSE chickens, while there was no difference (p>0.05) in α-ryr gene expression regardless of line studied. The β-ryr RQ results suggested that in PSE samples an alteration might occur in the regular ratio (1:1) of α-RyR/β-RyR normally found in avian muscles. These results provided the first evidence of PSE meat occurrence as a result of the differential expression of ryanodine receptor genes which might lead to an increased in Ca2+ availability at the cell milieu.
As proteínas α-RyR e β-RyR apresentam papéis distintos no mecanismo de excitação-contração com diferenças em seus mecanismos de ativação e respostas a ligantes. O RNA total de filé de peito (Pectoralis major m) com PSE (L*24h>53,0; pH 5,8) e não-PSE (44<"L*24h>53) de duas linhagens distintas, de corte e de postura, foram utilizadas para estudar a expressão gênica dos genes α-ryr β-ryr por PCR-em-tempo-real. Os valores médios de expressão gênicas relativas (RQ) foram inferiores (p<0,05) para em frangos PSE das duas linhagens quando comparadas aos frangos não-PSE. Por outro lado, não houve diferenças (p>0,05) na expressão do , independentemente da linhagem estudada. Os resultados de RQ para β-ryr indicaram nas amostras PSE, uma alteração na proporção (1:1) de α-RyR/β-RyR comumente encontrada em músculos de aves. Estes resultados originam a primeira evidência da ocorrência de carnes PSE como resultado de uma disponibilidade acentuada de Ca2+ no citosol pela expressão diferenciada de proteínas receptoras de rianodina.
RESUMEN
Soybean - Glycine max (L.) Merrill, cultivars Br-13 and Parana were germinated for 72 hours, with sampling every 6 hours. The effects of germination process on nutritional constituints (protein, lipid, total soluble carbohydrate) was studied. Analysis of variance and comparison of means indicated a significative increase in the protein content; decrease in the lipids and total soluble carbohydrate content up to 72 germination hours