To clarify the productivity of Sasa nipponica pasture, we conducted a cow-calf grazing study in the summer season. We determined the yearly changes in leaf mass, palatability and livestock weight of the pasture for six years. The leaf mass of the entire pasture increased yearly: the leaf mass of the predominant plant Sasa nipponica decreased, that of herbaceous plants increased slightly, and that of woody plants increased rapidly. We estimated the leaf mass available to cows from the mass of leaves found below the reachable height of cow’s mouth and the palatability of plants to cows. The available leaf mass in the first experimental year decreased by about half in the sixth experimental year. The grazing capacity of the pasture ranged from 168-200CD/ha. The weight of cows was almost maintained until the beginning of August, but it decreased thereafter. The daily gain of calves showed a value of more than 0.6kg for six years. It ranged 0.76-0.92kg until the beginning of August in the third year of use. In summer grazing, Sasa nipponica pasture has moderate livestock productivity until the beginning of August even in the sixth year.

A camera equipped UAV (drone) combined with image analysis was used for quantifying disease progression of northern leaf blight (NLB) and southern leaf blight (SLB) in maize. Early in the infection process when lesions were small, the correlation between a breeder’s rating and the relative Green Red Vegetation Index (rGRVI) in both NLB and SLB resistance was low. However, rGRVI showed a high correlation with the breeder’s rating for both NLB and SLB after lesions became larger as the disease progressed. In addition, calibration curves were prepared with standard maize varieties resulting in rGRVI estimates that correlated highly with the breeder’s rating. Thus, it was suggested that NLB and SLB resistance can be evaluated using rGRVI as an index and was more efficient than traditional scoring methods and can increase the number of varieties evaluated.

Red top (Agrostis alba L.) is a grass with good moisture endurance and persistency. However, the early growth of red top is slow. On the other hand, festulolium (x Festulolium braunii) is a grass with good moisture endurance and early growth. So red top and festulolium are mixed to introduce into abandoned paddy fields. The aim is to establish a mixed sown pasture of red top and festulolium so as to obtain a good yield immediately after renovation and to have a high level of persistency in abandoned paddy fields. In this study, we investigated the change of the vegetation and the yield of mixed sown pasture of red top and festulolium to compare with that of single-grass sown red top pasture. As a result, when 1kg/10a seeds of festulolium and 3kg/10a seeds of red top were mix-sown, it was possible to increase the yield immediately after renovation and to suppress weeds. As pasture was used for grazing, red top coverage increased and festulolium coverage decreased gradually. We found that the mixed sown pasture of red top and festulolium shifted to a pasture dominated by red top three years after renovation.

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