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Mango cultivation is one of the key economic agricultural activities of fruit in Brazil. In Southern Brazil, mango presents vulnerability thanks to its frost sensitivity, indicating the relevance of climate studies to improve the production and agricultural techniques, in the context of sustainable agriculture and climate change. Agroclimatic zoning should be one of the first information to be considered when starting its cultivation. The objective of this study is to carry out climatic risk zoning for mango tree (Mangifera indica) in the basin of Parana River III, Brazil. Meteorological data from 43 stations, from 1976 to 2018, were used. The climatic risk analysis was based on the requirements of the mango for precipitation, water balance, average annual temperature, and frost tolerance. The occurrence of frosts is the key restrict factor for production in the area of study. This meteorological factor restricted mango cultivation in the central-eastern portion of the basin. In other areas, the risk is present but the mango cultivation is recommended. Key words: Climate aptitude, climate variability, agricultural planning.

The hectoliter weight or test weight is an important wheat quality parameter for international trade and is traditionally evaluated on devices with a volume of 250, 500, 1000 or 1100 ml. At the experimental level, especially in crop improvement and in greenhouse studies, the amount of grain is often insufficient to determine hectoliter weight. The present work aimed to evaluate the feasibility of using a new 15.30 ml microchondrometer to evaluate hectoliter weight. The testing process was carried out in two steps: (i) To evaluate the need to compress wheat grains inside the microchondrometer cylinder with weights of 0, 4.4, 8.8 and 13.2 kg, and (ii) To verify the effect of different piston weights (4.0, 9.52, 17.56, 28.44 and 31.69 g). A comparison of four compression treatments and five piston weights between 250 ml and 15.30 ml chondrometers were performed by Spearman's correlation coefficient and t-test. The results showed a highly significant correlation coefficient (r=0.99) between the two apparatus and lack of significance for compression and piston weights. The 15.30 ml microchondrometer, in addition to allowing better characterization in small grain samples, will also help to discard unwanted genotypes early in the selection process. Key words: Plant breeding, grain density, genotype screening.