Maria Toader, Emil Georgescu, Alina Maria Ionescu and Paula Ionela Năstase
The purpose of this paper is to study and to analyze the chemical composition and energetical value (caloric) of 8 maize hybrids (Fundulea 376, Olt, Bărăgan, P0216, PR35T36, PR35P12, Feria and Rapsodia) tested under field conditions in a farm from, Rovine village, Ialomita County, under non-irrigated conditions, on 2016-2017. For all hybrids the same cultivation technology was applied. Sowing was carried out between April 20-27, for both years, with a density of 50,000 germinable grains/ha and in September were harvested. The analysis of the productivity elements showed that: the average length of cobs was between 20 to 23 cm; number of rows/cobs ranged from 14 to 18; the number of grains/cobs oscillated between 704 grains/cobs at Baragan hybrid, up to 890 grains/cobs at PR35T36; the Thousand Grain Weight (TGW) recorded values of over 300 grams for tree hybrids PR35T36, P0216, PR35P12; the density of plants at harvesting, main factor for yields grains, oscilated from 42,650 plants/ha in 2016 for Olt hybrid to 49.000 plants/ha at P0216 hybrid in 2017; the grains yields was of 8.4 t/ha at Baragan hybrid and 13.9 t/ha at PR35T36 hybrid. Regarding quality indicators of yields resulted: the hectolitre mass averaged 72.7 kg/hl with variation limits of 70.3 kg/hl and 76.8 kg/hl and the moisture varied between 11.90% and 14.50%. Chemical composition is followed: 10.70-12.70% proteins; 3.7-4.3% lipids; 70.00 - 70.70% glucids. Based on these results , it has been calculated the energy values (caloric). This oscillated between 369.3 kcal./100 grams of Rapsody hybrid and 388.38 kcal. of P0216 hybrid. It can be noticed that the year 2017 was a very favorable year for maize crops in the analyzed area, which led to better results for all the productivity elements, grains yields and chemical compozition for all 8 tested hybrids. Also, we can observed the higher energy value on 2017 by comparison with 2016.
Emil Georgescu, Maria Toader, Alina Maria Ionescu, Lidia Cană and Luxiţa Râşnoveanu
In the last years sunflower become one of the most important crops in Romania. The most of the surface cultivated with sunflower from our country is located in south and south-east and, in many cases, sunflower is cultivated after maize. As result the attack of the maize leaf weevil (Tanymecus dilaticollis Gyll) at sunflower plants has increasing. The attack is dangerous when sunflower plants are in first vegetation stages (BBCH 10-BBCH 14). Similar with maize crop, sunflower seeds treatment with neonicotinoids were generalized after 2007. As result of the EU directive 485/2013, no active ingredients remain available for sunflower seeds treatment, against T. dilaticollis, in Romania. The researches from the last years were orientated for finding of the possible alternatives for seed treatments, in eventuality of permanent ban of neonicotinoid insecticides, after 2018. Because of the variability of climatic conditions from the field, during spring period, researches concerning effectiveness testing of sunflower seed treatments, in green house conditions, using high pest pressure is a good method to evaluate influence of the different active ingredients to control T. dilaticollis adults. In this experiment it has tested three doses of cyantraniliprole active ingredient (7.5, 10.0 and 12.5 l/to) and three neonicothinoid active ingredients (imidacloprid, clothianidin, thiamethoxam). Sunflower seeds were placed in plastic pots. After plants emergence the insects were added in pots. At each pot it has added 20 adult insects, collected from the field. Each day, it has recorded insect mortality. At 8 days from the start of the experiment, it has assessed attack intensity of the adult insects on sunflower plants. The attack was evaluated using a scale from 1 (plant not attacked) to 9 (plant complete destroyed). In conditions of high pest pressure (4 insects/plant) the attack intensity of T. dilaticollis at sunflower plants was ranged from 3.35 in case of variant treated with clothianidin and 8.50 in case of untreated plants. Lower attack intensity of the pest at sunflower plants it has registered in case of variants treated with imidacloprid and thiamethoxam (I=3.58 and 3.50). Plants emerged from the untreated seeds were destroyed by the insects, at 8 days from the start of the experiment.