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  • Training and maintaining spindle crowns in cherry production
    51-53.
    Views:
    222

    In cherry production all over the world, intensification of the technology is the main objective of research. Small crowns and high planting densities are aimed to attain high yields per hectare and easier harvesting. Rootstocks of reduced vigour for cherries are more difficult to find than in other fruit species, and the rejuvenation of fruiting structures by pruning is aggravated by the reduced vigour. Intensity of the technology ought to be achieved by a thoughtful application of the technological elements (timing of pruning by various intensity) moreover, by finding different policies for individual varieties. Sweet cherry varieties dominating the assortment proved to be very variable regarding their growing habits. In our experiment, we dealt with the slender spindle and free spindle forms, and how to train the trees to develop and to maintain the desirable form depending on the respective variety in order to achieve the right load of flower buds and yields repeatedly. In this paper, we examine the most important practical issues with the training and maintaining of the crowns of cherries with circular projection and central axis grafted on Prunus mahaleb rootstocks

  • Modelling and comparing two canopy shapes using FEM
    71-74.
    Views:
    112

    Central leader and Vase form canopy models were built using FEM. Their main characteristics were chosen to be the same. The models were virtually exposed to the effect of steady-state horizontal forced vibration in the frequency range of 0-20 Hz. Acceleration-frequency curves were calculated and drawn to find the best frequency values for the effective detachment and also to see the acceleration differences in the limbs. For the same purpose the direction of shaking was also changed. It was found that for the Central leader canopy shape multidirectional shaking would bring uniform detachment while for the Vase form trees also the unidirectional shakers were appropriate. The acceleration achieved for the Vase form models were much higher than for the Central leader type. The acceleration-frequency curve of the shaker unit can be used to find the best frequency for shaking.

  • Relation between the germination and infection ratio on Sida hermaphrodita L. Rusby seeds under hot water treatment
    117-121.
    Views:
    174

    Sida hermephrodita or virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through between ten and twenty years. Additionally, the plants have a lot of uses and benefits for instance it can use it as a fodder crop, honey crop, ornamental plant in public gardens. It has favorable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in base stage of domestication therefore has a serious disadvantage the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seed/acre instead of 10-20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a disposable ,basically wild Sida population. We examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenus or endogenus infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65, 80 and 95 oC), 29,33 to 46% germinated of the seeds collected from the population of S. hermaphrodita in Debrecen. The average germination for all season was 5-10 % wihitout treatment and rised using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46 %) after the hot water operation in spite of the previus studys (Spooner 1985; Chudik et al. 2010; Doliński R. 2009.). We discovered that there are a distinguished close relationship between the seeds collecting time and the infection, as well as germination percentage. Thus, 2009 season was the most favourable in case of contamination (control:17,33 and 80 oC treatment:0%) as well as germination percent. It could be concluded that, the best season for our findings was 2009 due to autumn harvest of Sida seeds. In our oppinion, the autumn harvesting should be the best time to overcome the problem of the low germination and high infection percentage.

  • A simple model for fruit tree shaking harvest
    33-36.
    Views:
    198

    A tree structure model was composed of trunk and main roots. It included a mass, spring and damping element, all of them reduced to the external end of the main roots. The model parameters, such as virtual turning centre, reduced mass, spring constant and clamping coefficient were measured on a real cherry tree. The model was than virtually shaken at 80 cm trunk height and acceleration and displacement amplitudes versus shaking frequency were calculated. The real cherry tree was shaken also at 80 cm trunk height by an inertia type shaker machine and the same data were recorded. The acceleration amplitude vs. frequency and displacement amplitude vs. frequency functions were similar for the virtual and real tree which proves the ability of the model. Power demand and specific power demand was then calculated in function of shaking frequency. The diagrams show that the shaking frequency of 12-14 Hz, of the practice is not the most efficient concerning amplitude, but is probably necessary from the point of view of acceleration needed to detachment of fruits.

  • Effects of salinity stress induced by hot spring water on tomato growth, yield and fruit quality under hydroponic cultivation in Japan
    23-28.
    Views:
    111

    The objective of this research was to test hot spring water as a source of salt to improve tomato quality under the hydroponic system. This research was conducted at Yamagata University, in Japan from February to July 2017. Salt stress was induced using salts of hot spring wastewater collected from Yupoka Onsen (Tsuruoka, Japan). The treatments were EC 2, 4, 8 12, and 16 mS/cm which were arranged in a Randomized Complete Block Design (RCBD) with five replications. Tomato plants were grown at EC 2 until flowering and then subjected to different EC concentrations until harvesting. The data were collected on plant growth parameters and fruit quality. Fruits were harvested at the red stage until the 5th truss. The results showed that fruits' Soluble Solids Content, organic acid, Nitrate contents and Sugar: Acid ratio increased significantly at EC 16 mS/cm and in the upper trusses compared to EC 2 and in the lower trusses. In contrast, fruit weight significantly decreased at EC 16 mS/cm and in upper trusses. Leaf thickness, size and SPAD, and specific leaf weight significantly declined at EC 16 mS/cm and upper leaves compared to EC 2 and in lower leaves. Plant height started to decline significantly after three weeks of treatment at EC 16 compared to EC 2.