Response of seeds and pollen of Onobrychis viciifolia and Onobrychis oxyodonta var. armena to NaCl stress

Sainfoin (Onobrychis viciifolia Scop.) is an important forage legume crop with 52 species adapted to dry and poor soils in Turkey, but little is known about the effects of salinity on germination and seedling growth in arid and semiarid regions suffering from salinity problem. The seeds and pollen of two species of sainfoin O. viciifolia and O. oxyodonta var. armena (Syn: O. armena) were exposed to 0, 5, 10, 20 and 30 dS m-1 of NaCl under in vivo and in vitro conditions and evaluated for germination under salt stress by comparing germination percentage, mean germination time, root and shoot length, fresh and dry seedling weight and dry matter. Increased salinity levels generally resulted in decrease in all traits except time to germination, dry seedling weight and dry matter, which increased at high salinity levels. O. viciifolia seeds germinated and grew more rapidly compared to O. armena seeds under NaCl stress. No decrease in germination and seedling growth up to 10 dS m-1 was recorded. On the other hand, there was a clear difference for germination and seedling growth between in vivo and in vitro conditions. Lower values were obtained from in vitro experiments; suggesting that mineral salts, sucrose and agar may have resulted in higher osmotic potential inhibiting germination and seedling growth of species compared in vivo conditions. Decrease in pollen germination with increasing salinities was very sharp, indicating that pollen germination had higher sensitive to salinity. But, pollen grains of O. armena germinated rapidly compared to O. viciifolia. The results emphasize that in vivo experiments could be used for screening of NaCl tolerance in sainfoin cultivars without expensive chemicals and sophisticated equipments, but pollen germination is more appropriate for its wild relatives

Commercial farmers’ strategies to control water resources in South Africa: an empirical view of reform

This article shows how large-scale commercial farmers, individually and collectively, are responding to land and water reform processes in the Thukela River basin, KwaZulu-Natal, South Africa. With a high degree of innovative agency, commercial farmers have effectively executed four strategies, enabling them to adapt and use their access to resources to neutralize multiple water reform efforts that once promised to be catalysts for inclusive change in the post-apartheid era. It is likely that policy alone will not facilitate the envisioned transformation, if local practices are not sufficiently understood and anticipated by the governmental officials charged with the implementation of water reform processes

Evaluation et homologation de variétés issues des vergers à graines de l'Etat - Programme 2016

This report shows the work done in 2016 by Irstea, INRA, ONF and CNPF in the frame of a joint research programme dedicated to improved variety testing. Three species or groups of species are involved: Douglas-fir, larches and ash. With regard to Douglas-fir, the actions aim to enlarge the common network of comparative trials and compare the performance of the 8 French varieties for survival, health, growth, branching, cold hardiness and drought resistance. For larch, the results mainly concern the performance of hybrid varieties at the adult stage (12 to 20 years after planting). The studied traits include survival, resistance to heat and drought, growth in height and diameter, stem straightness, and resistance to larch canker. The work dedicated to ash mainly concerns resistance to Hymenoscyphus fraxineus.Ce rapport présente les actions entreprises en 2016 par Irstea, l'INRA, l'ONF et le CNPF dans le cadre de l'évaluation des variétés issues des vergers à graines de l'Etat. Elles concernent 3 essences : Douglas, mélèzes et frêne commun. Pour le Douglas, les principales actions visent, d'une part, à compléter le réseau de plantations comparatives et, d'autre part, à comparer les performances des 8 variétés françaises pour la survie, l'état sanitaire, la croissance en hauteur et en diamètre, la forme, l'acclimatation au froid et la résistance à des stress hydriques. Pour le mélèze, de nouveaux résultats permettent de comparer des variétés hybrides et des espèces parentes, françaises et étrangères, au stade adulte (12 à 20 ans après la plantation). Les caractères étudiés incluent la survie, la résistance à la canicule, la croissance en hauteur et diamètre, la rectitude du tronc et la résistance au chancre. Les travaux relatifs au frêne concernent essentiellement la vulnérabilité à la chalarose

Evaluation et homologation de variétés issues des vergers à graines de l'Etat - programme 2015. Rapport final

This report shows the work done in 2015 by Irstea, INRA, ONF and CNPF in the frame of a joint research programme dedicated to improved variety testing. Four species or groups of species are involved: Douglas-fir, larches, Norway spruce and ash. With regard to Douglas-fir, the actions aim to enlarge the common network of comparative trials and compare the performance of French varieties for survival, health, growth, branching, cold hardiness and drought resistance. For larch, the results mainly concern i) performance of hybrids versus non-hybrid progenies, ii) the variation of hybrid percentage over time, from the seed lot to the thinned stand and iii) the origin of the clones that compose the two French seed orchards of Sudeten larch. At last, across site analyses give information about the worth of a seed orchard of Norway spruce (Rachovo provenance).Ce rapport présente les actions entreprises en 2015 par Irstea, l'INRA, l'ONF et le CNPF dans le cadre de l'évaluation des variétés issues des vergers à graines de l'Etat. Elles concernent 4 espèces : Douglas, mélèzes, épicéa commun et frêne. Pour le Douglas, les principales actions visent, d'une part, à compléter le réseau de plantations comparatives et, d'autre part, à comparer les performances des variétés pour la survie, l'état sanitaire, la croissance en hauteur et en diamètre, la forme, l'acclimatation au froid et la résistance à des stress hydriques. Les résultats liés aux mélèzes concernent principalement i) la comparaison de descendances hybrides et d'espèces parentales, ii) l'évolution du taux d'hybrides entre les lots de graines, la pépinière et le jeune peuplement et iii) la détermination de l'origine des clones composant les vergers français de mélèze d'europe 'Sudètes'. Enfin, une analyse multisite a permis d'évaluer les produits du verger d'épicéa Rachovo pour des caractères d'adaptation, de vigueur et de branchaison