Sunflower Stalk Diseases Initiated Through Leaf Infections

From a Single Leaf of Sunflower

When single leaves attached at a given node were allowed to carry on photosynthesis in 14CO2 for 30 min, younger plants showed a higher proportion of upward translocation than did older plants. Downward translocation of 14C-photosynthate was stimulated by ATP pre-treatment of the translocating leaf, while upward translocation was not affected by ATP. A similar phenomenon was observed in the tra...

Vertical-stalk Flapping-leaf Generator for Wind Energy Harvesting

We study a parallelized flapping piezo-leaf generator for harvesting ambient wind energy and demonstrate an initial design. We fabricated prototypes in various configurations and performed a series of experiments to study performance trends. We propose a novel vertical-stalk L-shape design that exhibits improved output power density over horizontal piezoelectric configurations. While a signific...

Effect of head removal on leaf senescence of sunflower.

Greenhouse and field studies examined the effect of flower or seedhead removal on leaf senescence and associated changes in sunflower (Helianthus annuus L.) plants. At intervals during seed development, selected leaves (leaves 6 through 8 from the top in the greenhouse and leaf 7 from the top in the field) were harvested and analyzed for chlorophyll, specific leaf weight, N, P, soluble protein,...

Rapid estimation of sunflower leaf area from linear measurements

Mycosphaerella leaf spot diseases

By the end of the 1980s, black leaf streak disease caused by Mycosphaerella fijiensis was present in all continents where bananas or plantains were grown, although distribution in some regions was limited to a few countries. In this presentation, the spread of the disease during the 1990s in several countries and regions, and the important socio-economic consequences are discussed. From 1990 to...