RESULTS REGARDING THE TOLERANCE TO THERMO-HYDRIC STRESS OF SOME POTATO LINES CULTIVATED ON THE SANDY SOILS FROM THE SOUTH OF OLTENIA

In this paper are presented the results regarding the physiological reactions of the 11 potato lines studied, on vegetation phenophases, in order to determine their tolerance to the thermo-hydric stress characteristic of the sandy soils area in the south of Oltenia. During the vegetation period, determinations were made with the LC Pro SD portable device, which focused on active solar radiation in photosynthesis, photosynthesis rate, air temperature, leaf transpiration rate and correlations established between these physiological parameters, specific climatic conditions of 2020 and production of potatoes obtained under these conditions. Between the physiological processes of photosynthesis and foliar transpiration, registered at RDSPCS Dăbuleni, a positive, distinctly significant correlation was established. The lines with higher tolerance to thermo-hydric stress showed an intense assimilation, directly proportional to the intensity of foliar transpiration. Lines L 15-1876 / 7 and L 18-1828 / 6 were noted in this regard. At the opposite pole, the lowest physiological activity was recorded on the lines L 1901/11 and L 1901/6

RESULTS REGARDING THE FERTILIZATION OF THE SUNFLOWER CROP WITH AN EFFLUENT OBTAINED BY WASTEWATER TREATMENT

The research was carried out in 2020 on the sunflower crop grown in sandy soils in southern Oltenia and aimed at the influence of fertigation with an effluent obtained by wastewater treatment, compared to conventional fertilization and irrigation with normal water from surface water sources. The obtained results showed the positive influence, on the nutritional status of the plant, of ensuring the dose of nitrogen in the vegetation by fertigation with purified water, applied fractionally in 2-3 steps (Nt-3.5%; Pt = 0.35% Kt = 2.7%), compared to classical fertilization and irrigation with normal water from surface water sources. It was noted with the best results on production (4427.5 kg / ha) and the weight of one thousand grains (69 g), the variant in which the dose of 70 kg N / ha, required in vegetation, was ensured by irrigation with treated water,  applied fractionally in two doses of 50%, starting with the phase of 5-7 leaves.Â

ASPECTS REGARDING THE PHYSIOLOGICAL PARAMETERS IN SOME LOCAL POPULATIONS OF CAPSICUM ANNUUM SSP. GROSSUM UNDER STRESS CONDITIONS

In this paper are presented results regarding the physiological behavior of some local populations of Capsicum annuum ssp. grossum, cultivated compared to the control variety Cornel on sandy soils from the Research and Development Station for Plant Culture on Sands, Dăbuleni. The researches focused on the effects of thermal stress on the processes of photosynthesis and foliar transpiration, as well as on the productions made in pepper culture. The results obtained underlined the importance of correlating the physiological processes in pepper plants with environmental factors and the yields obtained. Under conditions of heat stress, all local populations analyzed showed values of photosynthesis above the values recorded at the control variant (Cornel variety). The water lost through foliar transpiration was efficiently recovered by the studied local populations, between transpiration and pepper production being established a positive correlation, significant from statistically point of view

STUDY ON MONITORING AND COMBATING THE ATTACK OF TUTA ABSOLUTA ON TOMATOES CULTIVATED IN PROTECTED SPACES IN SOUTH ROMANIA

Lately, for tomatoes grown in protected spaces there is another limiting factor, an extremely dangerous pest (Tuta absoluta). Tuta absoluta is an extremely dangerous polyphagous insect. It belongs to the Gelechiidae family, Lepidoptera order. The pest is a small butterfly (moth), 5-7 mm long, brown with shades of dark gray. The larva is white-green, with a black head and a brown pupa. It has 12 generations per year. An adult female can have up to 250 eggs during her lifetime. The life cycle is completed in 30-40 days, but largely dependent on environmental conditions. It has 4 larval stages, wintering as an egg, pupa or adult. Moths are more active during the night, during the day being hidden among the leaves. Starting with 2020, in some protected spaces from well-known vegetable basins for growing tomatoes in South Romania, a study was initiated on monitoring the attack of Tuta absoluta. Preliminary results show that the pest is extremely harmful (sometimes the damage to tomato crops can be very high, even compromising the crop), and that chemical control measures, in the absence of agrophytotechnical measures, do not ensure good effectiveness

THE INFLUENCE OF CLIMATE CONDITIONS ON THE NUTRITIONAL QUALITY OF SOME POTATO LINES TESTED IN CULTURE ON SANDY SOILS FROM SOUTHERN OLTENIA

In this paper are presented the results regarding the biochemical composition of the 7 potato lines studied at Dăbuleni Research-Development Station for Plant Culture on Sands in conditions of thermo-hydric stress. The obtained results highlighted differentiations depending on the genotype and depending on the climatic conditions of the 2 years of study (2020-2021). A high content of total dry matter, above the average of 22.87% presented 4 of the 7 potato lines studied, the highest values being recorded at line L 1901/11 (27.09%). Starch, the main biochemical component of potato tubers, showed values between 12.86% in 2020 and 13.08% in 2021, the highest average values of starch content in tubers being determined in line L 1895/1. The vitamin C content was higher in all the lines studied in the climatic conditions of 2021 year

Sweet potato, a perspective crop for the sandy soil area in Romania

Due to the low natural fertility and climatic conditions characterized by excessive heat and insufficient precipitation, the sandy soils area in southern Oltenia can be characterized as a disadvantaged agricultural area, with farmers having a small variety of crops to ensure the exploitation of the soil in profitable conditions. In the context of climate change, in order to obtain high, safe and stable productions, it is necessary to choose the range of species and plant varieties with high adaptability to the climatic and soil conditions, in this context, Research-Development Station for Plants Culture on Sands Dăbuleni conducting research on the adaptability and profitability of sweet potato culture. Considering that in the tropical and subtropical regions completely replace the potato, F.A.O. mentions sweet potatoes on the 7th place in the world among agricultural crops. Currently, this culture is less known in Romania. With the increase in the import of vegetables, the interest of Romanian consumers for this species of tropical origin has increased. Taking into account these considerations, the researches aimed at establishing the technology of sweet potato cultivation on sandy soils and the biological and biochemical peculiarities of this species. The obtained results were similar to those in the literature, the differences being due to the studied genotypes and to the climatic conditions of the crop year. It is a drought resistant species with vigorous growth and high productivity (20-40 t / ha). Sweet potato is a species of perspective for Romanian vegetable growing, with special nutritional qualities and economically profitable

STUDY OF SOME PEPPER GENOTYPES (Capsicum annuum L.) UNDER THE CONDITIONS OF THERMAL AND WATER STRESS IN THE SOUTHERN AREA OF OLTENIA

In recent years increasingly many spoken of global climate change, desertification and aridity in many areas, such as the sandy soils in southern of the Oltenia area. Starting from the idea that the negative effect of temperature and water stress factors can be reduced by scientific and technological progress, it requires the collection and evaluation of genetic resources vegetable, adapted of conditions from southern Oltenia. In this regard, at CCDCPN Dăbuleni were followed in  the crop 4  cultivation of domestic pepper (Capsicum annuum L.): Isalnita 85 V, Andrada, Isalnita – Rovine, Amaradia

Issues regarding the ecological forestry reconstruction of the degraded land inside Podu-Iloaiei forest district, Iași county

Studies conducted by researchers in our country points out that most of the installed protective forest cultures on degraded land have as basic species black pine (Pinus nigra) and sylvester pine (Pinus silvestris). It should be noted that under massive regeneration and introduction under the shelter of the massive, in gaps created by extracting damaged pine specimens, of some genetically valuable native species, are an effective forestry method of transition for temporary forest ecosystems to stable (areal) forest ecosystems, but also of increasing the stability and functional efficiency (of protection) of arboretum located in less favorable places (moderately eroded land and potentially sliding lands). Ecological forestry reconstruction actions that are mentioned in this paper are important for the recovery of the hydrological and antierosion protective capacity of these tree stands, but also for assuring their continuity on degraded lands, thus obtaining a more effective protection of the places next to forested areas

Utilization of the thermohydric stress in the psamosols area in Southern Oltenia through the cowpea culture

The area of psamosols in southern Oltenia is characterized by thermohydraulic stress, accentuated by the thermal resources recorded and by the poor hydrophysical properties of the soil. Higher capitalization of these lands has been an important concern both in the world and in our country, and the choice of plant species with increased drought resistance and low water consumption is a measure to counteract the negative effects of the drought. The humidity analysis of a psamosol, on the 0-125 cm profile, indicates a momentary supply of reduced water and a water deficit compared to the field capacity of -34.4 ... -65.5 m3 / ha. In order to obtain economic results on these soils, it is necessary to cultivate low-water plants, such as a cowpea (Vigna unguiculata L. Walp) that consumes about 4160 m3 / ha, compared to soybeans that have almost double consumption. The results obtained in 4 genotypes of cowpea highlight the daily average values of the plant's foliar sweating, in the blooming phase, ranging between 4.05 -5.23 mmol H2O / m2 / s, which correlated negatively with the level of grain production