Agrometeorological Requirements of Maize Crop Phenology for Sustainable Cropping—A Historical Review for Romania

Identifying regional variations and agronomical records can turn into a function of magnitude and timing for sustainable maize production. The crop characteristics are directly related with the temperature and precipitation from the growing season. Therefore, the main aim of this study was to highlight maize crop requirements from the most suggestive records from Romania. A literature search was performed based on keywords related to both maize crop and agrometeorological requirements. After the evaluation of the temperature requirements on maize phenology’s principal stages, some inconsistencies were identified. These are related to the leaf development stage and the development of the fruit stage, where the minimum temperature interval overlaps with the optimum. A wide variety of assessments were also made, taking into account mainly the monthly temperature and precipitation requirements. The number of principal growth stages assessed differed greatly from one source to another. The growth degree days has been incoherently expressed and calculated, and these details must be taken into account for developing further models. The results regarding phenology aim to propose the setting up of comparable records at a regional (PannEx area) and global scale. This review will help to develop new climate projections in Romania in the climate change context through the project Agroclim.

COMPARISON OF SPRING AND SUMMER SOWING OF SUGAR BEET GENOTYPES AT DIFFERENT HARVEST DATES TO SHIFT FROM TRADITIONAL CROP TO CASH CROP IN CENTRAL IRAN

This study was carried out in Karaj, Iran in 2017 and 2018 to assess the efficacy of summer sowing (June 22) versus spring sowing (April 20) of six sugar beet genotypes at three harvest times (October 13, November 2, and November 23) via the measurement of catalase (CAT), malondialdehyde (MDA), and agronomic traits. Results showed that in both sowing dates, higher growth and temperature were related to higher CAT activity and MDA content, and the maximum MDA and CAT activity were observed in 1700−1900 growth degree days (GDD). Genotypes responded to the shortening of the growth period differently. The best genotypes for summer sowing were found to be ‘Paya’, ‘IR7’, and ‘Pars’ when a combination of the least response to delayed sowing and the highest root yield in the summer sowing conditions was considered. Compared to the spring sowing, the summer sowing decreased white sugar yield (WSY) of all cultivars by 28.3−50.5% in the first year and 5.3−32.4% in the second year. ‘Paya’ and ‘IR7’ were the most capable cultivars in preserving WSY so that they maintained 70% of their yields. In addition, the genotypes exhibited their highest WSY at the November 23 harvest date so that root, raw sugar and white sugar yields were 41.21, 6.35 and 5.02 t ha−1 higher at the November 23 harvest date than at the October 13 harvest date, respectively. Based on the results, if summer-sown sugar beets are considered as a cash crop in rotation with grains and there is no limitation on water supply, it can then be recommended to farmers as it can make good profits for them.

Effects of Climate on Fruit Growth and Development on Olive Oil Quality in Cultivar Carolea

Trees of the olive (Olea europaea L.) cultivar Carolea grown in Calabria (Italy) in three sites with different main climate traits (temperatures, rainfall, Growth Degree Days seasonal variations) were studied for three years to see the ripening time course and quality of the oils. The optimal harvesting time for obtaining the best-quality olive oils was defined for each site. The effect on quality indexes of three harvesting periods was also considered, linking this to the observed various thermal regimes. The different climates largely affected the growth and the development of fruits and the quality of obtained oils. Lower temperatures and higher rainfall slow down fruit growth and development and delay ripening. Olive oils of good quality (free acidity, fatty acid composition, antioxidant components and oxidative stability were obtained in the site with lower temperatures and higher rainfall when fruits were still yellow-green ripe and had a detachment index between 1.9 and 1.5. Climate change, evidenced by rising temperatures, led to the movement of olive groves from the high-temperature coastal plain to the intern foothills.

Evaluation of dry matter accumulation in triticale by different sigmoidal growth models in west anatolia of turkey

Monitoring biological growth of field crops is important for planning and timing agricultural practices. In order to assess biological growth pattern of dry matter accumulation in triticale Egeyildizi triticale variety were grown in ?anakkale conditions in 2012-2013 and 2013-2014 growing seasons with continuous plant samplings from seedling emergence until seed maturation. Gompertz, Logistic, Logistic Power and Richards growth models are fitted to actual growth data and their predictions were compared. Results suggested that all sigmoidal growth models successfully explained triticale dry matter accumulation over 98 % R2 values and low mean square errors, Richards model fitted best for both years with an R2 value over 99 %. Dry matter accumulation were also investigated as a result of average temperature, precipitation, growth degree days and cumulative growth degree days with stepwise regression. Rresults indicated that average weather temperature had a similar pattern across both growing seasons and had a major influence on dry matter accumulation. Since Richards sigmoidal growth model may be adequately described growth pattern of triticale by generally high R2 with lower Mean Square Error (MSE) values.

Influencia de la temperatura en la floración de Quercus en el sur de Galicia (Ourense y Vigo, 1994-98)

Los requerimientos necesarios para que las plantas sobrevivan a condiciones climáticas adversas son satisfechos mediante el uso de adaptaciones fisiológicas. Así, las plantas leñosas de la zona templada, para prevenir el congelamiento del agua intracelular, ralentizan su crecimiento hasta casi paralizarlo, entrando en un estado fisiológico denominado "dormancia". Muchos autores indican que el final de la fase de dormancia requiere un período de bajas temperaturas seguido de otro con temperaturas más altas. En el momento en el que los actimulos de frío y de calor son completados, se produce la floración. El objetivo de este estudio es conocer la influencia que un parámetro climático como la temperatura ejerce sobre Quercus en el sur de Galicia, para poder predecir el inicio del período de dormancia, su duración y los consecuentes requerimientos de frío y calor, para que la floración tenga lugar. En este sentido hemos elegido dos zonas con parámetros de temperatura diferentes: una zona con temperaturas suaves, Vigo y otra con temperaturas mas frías, Ourense. El monitorizaje ha sido llevado a cabo mediante el uso de un captador volumétrico tipo Hirst LANZONI VPPS 2000, de recambio semanal. Quercus comienza su período de polinación en el mes de marzo, se inicia durante la primera quincena en Vigo, y unos pocos días más tarde se produce en Ourense. Durante los cuatro años de estudio, para superar el período de dormancia Ourense necesitó una media de 778 unidades de frío (Chilling Hours) y Vigo un menor requerimiento con solamente 458 CH. En el caso del actímulo de calor, Ourense presenta el menor requerimiento con una media de 352 GDD (Growth Degree Days) y Vigo alrededor de 450 GDD.