Dehydration tolerance and storage sensitivity of Campomanesia adamantium seeds

Cultivating native fruit species depends on the existence of technical and scientific information. In this context, studies on propagation are the basis for other investigations. Campomanesia adamantium is propagated by seeds, and quality seeds guarantee the formation of high-performance plants in the field. This study aimed to analyze the dehydration tolerance and storage sensitivity of Campomanesia adamantium seeds. Experiment 1 evaluated the physiological quality of seeds with moisture contents of 43, 30, 26, 23, 18, 15, and 5%. Experiment 2 determined the seed moisture content, germination, and vigor of seeds depulped and immediately stored at 16 and 25°C, for 25 and 50 days. Seed viability was not affected by dehydration up to 15% of moisture content but decreased at 5%. Drying was accompanied by reduced seed vigor and seedling mass. The germination of unstored seeds was superior to stored ones. Storage at 16°C for 25 days was promising to maintain seed viability. The seeds showed intermediate recalcitrant behavior. Dehydration below 30% reduced vigor, while 5% affected viability. Campomanesia adamantium seeds can be stored for 25 days at 16°C in permeable packaging that maintains approximately 10% of moisture, with germination higher than 60%.

Dinâmica populacional de ovos e lagartas e parasitismo de ovos de curuquerê-do-algodoeiro por Trichogramma pretiosum em cultivares convencionais e transgênica de algodoeiro / Population dynamics and track of eggs and egg parasitism of cotton leafworm byTrichogramma pretiosum cultivars in transgenic and conventional cotton

A introdução de novas cultivares de algodoeiro na região Centro-Oeste do Brasil resultou em significativo aumento de produtividade, porém a utilização de técnicas inadequadas de cultivo trouxe muitos problemas a campo, como a maior incidência de pragas, doenças e plantas infestantes. Com o objetivo de estudar a dinâmica populacional de ovos e lagartas e o parasitismo natural de ovos de curuquerê-do-algodoeiro por Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae), em diferentes estágios fenológicos de cultivares convencionais e transgênica (Bollgard I) de algodoeiro, foi realizado um experimento no período de dezembro de 2007 a abril de 2008 em Ipameri, Goiás, Brasil. O delineamento experimental foi o de blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos foram constituídos pelas cultivares de algodoeiro convencionais DeltaOPAL, FMX 966, FMX 993, FMX 910 e a transgênica NuOPAL. Alabama argillacea Hübner (Lepidoptera: Noctuidae) ovipositou em todas as cultivares, não se observando diferença em relação à preferência para oviposição. Em relação ao número médio de ovos de A. argillacea parasitados por T. pretiosum, também não houve diferenças entre as cultivares. Nas cultivares convencionais, lagartas pequenas, médias e grandes ocorreram a partir dos 34 dias após a emergência das plantas até o final do ciclo, enquanto na cultivar transgênica foram encontradas apenas lagartas pequenas. A cultivar NuOPAL controla lagartas de curuquerê-doalgodoeiro desde os primeiros estádios larvais, ou seja, ainda pequenas, e não interfere no parasitismo de ovos por T. pretiosum em relação as demais cultivares.

The introduction of new cotton cultivars in the Midwest region of Brazil resulted in a significant increase in productivity, but the use of inappropriate farming techniques brought many problems to field, as the higher incidence of pests, diseases and weeds. The aim of this work was to study the population dynamics of eggs and larvae of cotton leafworm and natural egg parasitism of the pest by Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) at different phenological stages of conventional and transgenic cultivars (Bollgard I) of cotton was carried out this experiment from December 2007 to April 2008 in Ipameri, Góias State, Brazil. The experimental design was a randomized blocks with five trataments and four replications. The treatments consisting of the conventional cotton cultivars DeltaOPAL, FMX 966, FMX 993, FMX 910 and the cultivar transgenic NuOPAL. Allabama argillacea Hübner (Lepidoptera: Noctuidae) oviposited on all cultivars, not presented differences in relation to oviposition preference. Compared to the average number of eggs of A. argillacea parasitized by T. pretiosum, there were no differences between cultivars. In conventional cultivars, small, medium and large larvae occurred from 34 days after plant emergence until the end of the cycle, while in the transgenic cultivar were found only small caterpillars. Cultivar NuOPAL control cotton leafworm since the first larval stage, and does not interfere in egg parasitism by T. pretiosum compared with other cultivars.