Previsão da perda de solo na Fazenda Canchim - SP (EMBRAPA) utilizando geoprocessamento e o USLE 2D Loss of soil determination in Fazenda Canchim - SP (EMBRAPA) using geographic information systems and USLE 2D

Os modelos hidrossedimentológicos têm enorme potencial no Brasil para ser a melhor ferramenta de estimativa de perda de solo, devido principalmente a sua complexidade na descrição dos processos e sua robustez que os fundamenta. Entretanto, devido à necessidade de uma quantidade muito grande de informações requerida, aliada a dificuldades de adaptações desses modelos internacionais e necessidade de tempo e estrutura para criação de modelos nacionais, a Equação Universal de Perda de Solo (EUPS) e suas variações ainda são uma referência no Brasil para determinação de perda de solo. Neste trabalho, utilizou-se um atual modelo de cálculo do fator LS, o Software USLE 2D, em conjunto com o IDRISI. A aplicação foi feita na Fazenda Canchim da Embrapa Pecuária Sudeste; consistindo o primeiro trabalho desta natureza realizado nessa área com tais ferramentas. Os resultados obtidos mostraram-se coerentes com os tipos de solo, as declividades e a cobertura vegetal da área de estudo.<br>The hydrosedimentological models have an enormous potential in Brazil to be the best tool for the estimative of soil lost principally due to their complexity on description of the processes and the robustness that validate them. However, due to a need of a very big volume of required information in connection with the difficulties to adapt the international models and the need of time and structure to create national models, the Universal Soil Lost Equation (USLE) and its variations still are a reference in Brazil to soil lost determination. In this article, a new model to calculate the SL factor, the USLE 2D Software combined with the IDRISI were used. The inedited application was done in Southeast Cattle Breeding Embrapa's Canchim Farm, consisting on the first work of this nature done in this area with such tools. The results obtained were coherent to types of soil, slopes and vegetal cover in the area of study

Identification and functional study of a mild allele of SlDELLA gene conferring the potential for improved yield in tomato

Parthenocarpy, or pollination-independent fruit set, is an attractive trait for fruit production and can be induced by increased responses to the phytohormone gibberellin (GA), which regulates diverse aspects of plant development. GA signaling in plants is negatively regulated by DELLA proteins. A loss-of-function mutant of tomato DELLA (SlDELLA), procera (pro) thus exhibits enhanced GA-response phenotypes including parthenocarpy, although the pro mutation also confers some disadvantages for practical breeding. This study identified a new milder hypomorphic allele of SlDELLA, procera-2 (pro-2), which showed weaker GA-response phenotypes than pro. The pro-2 mutant contains a single nucleotide substitution, corresponding to a single amino acid substitution in the SAW subdomain of the SlDELLA. Accumulation of the mutated SlDELLA transcripts in wild-type (WT) resulted in parthenocarpy, while introduction of intact SlDELLA into pro-2 rescued mutant phenotypes. Yeast two-hybrid assays revealed that SlDELLA interacted with three tomato homologues of GID1 GA receptors with increasing affinity upon GA treatment, while their interactions were reduced by the pro and pro-2 mutations. Both pro and pro-2 mutants produced higher fruit yields under high temperature conditions, which were resulted from higher fruit set efficiency, demonstrating the potential for genetic parthenocarpy to improve yield under adverse environmental conditions