Agronomic and Environmental Benefits of Cover Crops in Northern Italy

Cover crops have a number of benefits (reduction of nitrate leaching and of soil erosion, control of weed seed bank, increase of soil organic matter and increase of cash crop yield), but these were seldom quantified in cropping systems of Northern Italy. This experiment aimed to quantify some of these effects, by comparing cover crop species and their management techniques

Functional Analysis of the Arlequin Mutant Corroborates the Essential Role of the ARLEQUIN/TAGL1 Gene during Reproductive Development of Tomato

Reproductive development of higher plants comprises successive events of organ differentiation and growth which finally lead to the formation of a mature fruit. However, most of the genetic and molecular mechanisms which coordinate such developmental events are yet to be identified and characterized. Arlequin (Alq), a semi-dominant T-DNA tomato mutant showed developmental changes affecting flower and fruit ripening. Sepals were converted into fleshy organs which ripened as normal fruit organs and fruits displayed altered ripening features. Molecular characterization of the tagged gene demonstrated that it corresponded to the previously reported TOMATO AGAMOUS-LIKE 1 (TAGL1) gene, the tomato ortholog of SHATTERPROOF MADS-box genes of Arabidopsis thaliana, and that the Alq mutation promoted a gain-of-function phenotype caused by the ectopic expression of TAGL1. Ectopic overexpression of TAGL1 resulted in homeotic alterations affecting floral organ identity that were similar to but stronger than those observed in Alq mutant plants. Interestingly, TAGL1 RNAi plants yielded tomato fruits which were unable to ripen. They displayed a yellow-orange color and stiffness appearance which are in accordance with reduced lycopene and ethylene levels, respectively. Moreover, pericarp cells of TAGL1 RNAi fruits showed altered cellular and structural properties which correlated to both decreased expression of genes regulating cell division and lignin biosynthesis. Over-expression of TAGL1 is able to rescue the non-ripening phenotype of rin and nor mutants, which is mediated by the transcriptional activation of several ripening genes. Our results demonstrated that TAGL1 participates in the genetic control of flower and fruit development of tomato plants. Furthermore, gene silencing and over-expression experiments demonstrated that the fruit ripening process requires the regulatory activity of TAGL1. Therefore, TAGL1 could act as a linking factor connecting successive stages of reproductive development, from flower development to fruit maturation, allowing this complex process to be carried out successfully

Candidate gene functional profiling during fruit development and ripening in apple

The physiological process of fruit development and ripening is the result of a functional gene interplay governing the formation of the features characterizing the fruit quality properties. Among the several physiological processes, the modifications occurring in the cell wall are the most relevant and important, for their impact in the maintenance of the general fruit quality as well as the management of the postharvest storage. Beside the specific gene activation over the fruit cycle, also the particular genetic constitution can play important controlling roles. To investigate the functional machinery involved in the control of fruit texture and ethylene production during fruit ripening, two different cultivars, such as Golden Delicious and Granny Smith, were selected and a specific set of samples were collected, processed and hybridized over an ad hoc designed custom microarray platform. The specific regulation of approximately 3800 genes involved in fruit ripening and regulatory process, together with their relative anchoring on a set of QTL intervals, will allow the simultaneous analysis of the genes differentially regulated among the different samples and their putative genetic control on these fruit quality traits. This study can thus represent a step forwards into the comprehension of the several mechanisms underlying the apple fruit quality, offering new opportunity for supporting the constitution of the most favourable apple ideotypes