Additional bacterial diseases

Bacterial wilt (Corynebacterium flaccumfaciens) has been registered in the USA, but its existence in Latin America is unknown. Drought and temp. more than 32 degrees C are favorable conditions for disease development. The bacterium infects plants through the seed and wounds on aerial plant organs and roots. Control measures suggested include cultural practices and the use of resistant var. Bacterial brown spot (Pseudomonas syringae pv. syringae) produces flecks or necrotic brown lesions on the stem and pods. The bacterium has a wide host range. For efficient disease control, adequate chemical products and the use of resistant var. are recommended. Bean wildfire (P. syringae pv. tabaci) occurs in different bean-growing regions of Brazil and Argentina. Lesions on leaves are small, necrotic, circular to angular, light to dark brown, and surrounded by circular bright halos. No specific control measures are known. The symptoms and damage caused by the disease are illustrated in color. A list of other bacteria pathogenic to beans is also included. (CIAT)El marchitamiento bacteriano del frijol (Corynebacterium flaccumfaciens), se registra en los EE.UU., pero se ignora si existe en America Latina. La sequia y las temp. superiores a 32 grados C son condiciones favorables para el desarrollo de la enfermedad. La bacteria infecta las plantas a traves de la semilla y de las lesiones en los organos aereos de la planta y en las raices. Se sugieren medidas de control como practicas culturales y el uso de var. resistentes. La mancha parda bacteriana (Pseudomonas syringae pv. syringae) produce puntos o lesiones necroticas de color cafe en el tallo y en las vainas. La bacteria presenta un amplio rango de hospedantes. Para un buen control de la enfermedad se recomienda el uso de productos quimicos adecuados y de var. resistentes. La quemazon del tabaco (P. syringae pv. tabaci) del frijol ocurre en diferentes regiones productoras de frijol de Brasil y Argentina. Las lesiones en las hojas son pequenas, necroticas, de forma circular a angular, de color cafe claro a cafe oscuro y rodeadas por halos circulares brillantes. No se conocen medidas especificas de control. Se ilustran a color los sintomas y danos causados por las enfermedades. Tambien se incluye una lista de otras bacterias patogenas al frijol. (CIAT

Novas linhagens do feijoeiro resistentes ao crestamento bacteriano comum

With the objective of incorporation of genetic resistance for common bacterial blight in commercial cultivars of bean, cultivars Carioca, Rosinha, Moruna, Rio Tibagi and Iguaçu, susceptible to the disease, were crossed with moderately resistant Great Northern Nebraska 1 sel. 27. Some of the crosses yielded segregates with levels of resistance superior to the source employed. Subsequently, these selections were intercrossed among themselves and with another blight resistant source P.I. 207-262 with the objective of accumulating and stabilizing higher levels of resistance, thus resulting in several lines with high levels of foliage resistance, in some cases accompanied by pod resistance and desirable agronomic characters.Visando à incorporação de resistência genética para crestamento bacteriano comum nas cultivares comerciais do feijoeiro, foram realizados cruzamentos entre cvs. Carioca, Rosinha, Moruna, Rio Tibagi e Iguaçu, suscetíveis à doença, com Great Northern Nebraska 1 sel. 27 que possui moderado grau de resistência. Alguns desses cruzamentos produziram segregantes com grau de resistência superior à fonte utilizada. Dos cruzamentos subseqüentes destas linhagens, feitos entre si e com outra fonte de resistência, P.I. 207-262, visando acumulação e estabilização de elevado nível de resistência, resultaram linhagens com alto grau de resistência foliar, acompanhado, em alguns casos, por resistência das vagens e características agronômicas desejáveis

Parametric Seismic Analysis of Tall Buildings with Different Geometry and Constant Plan Area.

In this study, seismic analysis of high rise building frames have been carried out considering four buildings of different geometrical plan but same area , three diaphragms and four seismic zones. In this way total 48 frames were analysed for 27 load combinations. STADD-Pro software has been used for analysis purpose. Structural analyses results are collected in terms of maximum moments in columns and beams, storey displacement, peak storey displacement which are critically analysed to quantify the effects of various parameters

Comparative Study on Thresholding

Criterion based thresholding algorithms are simple and effective for two-level thresholding. However, if a multilevel thresholding is needed, the computational complexity will exponentially increase and the performance may become unreliable. In this approach, a novel and more effective method is used for multilevel thresholding by taking hierarchical cluster organization into account. Developing a dendogram of gray levels in the histogram of an image, based on the similarity measure which involves the inter-class variance of the clusters to be merged and the intra-class variance of the new merged cluster . The bottom-up generation of clusters employing a dendogram by the proposed method yields good separation of the clusters and obtains a robust estimate of the threshold. Such cluster organization will yield a clear separation between object and background even for the case of nearly unimodal or multimodal histogram. Since the hierarchical clustering method performs an iterative merging operation, it is extended to multilevel thresholding problem by eliminating grouping of clusters when the pixel values are obtained from the expected numbers of clusters. This paper gives a comparison on Otsu’s & Kwon’s criterion with hierarchical based multi-level thresholding