The determination of the number of flowers has traditionally been performed manually, which is very laborious and time-consuming. Methods to rapidly quantify flowers might also be of interest to breeders who select plants with specific flowering characteristics ( Ohnishi et al. The knowledge of flowering is useful for the development and optimization of crop management practices. Fruit growers must continuously improve their orchard agricultural practices to meet consumer demand for better quality fruit ( Dobbs & Rowling 2006).įlower and fruit thinning are considered some of the most important cultural practices affecting fruit quality and cropping consistency ( Byers & Carbaugh 2002). Frequently, pear trees bloom abundantly and set too many fruits to optimize the fruit size and return bloom. Consistent production of the fruit of optimum size can only be accomplished when a proper balance between vegetative growth and fruiting is maintained ( Reginato 2002 Treder 2010). The size of the tree, in turn, determines the number of fruits it can produce while maintaining the desired fruit quality.
Since fruits develop from flowers, the yield-forming potential of trees, regardless of their size in a given year, depends primarily on the number of flower buds developed in the spring. The use of strong, well-branched nursery trees is a prerequisite for early and high yields ( Theron et al. That is why fruit growers look for nursery trees with a strong leader and an extensive crown with many lateral shoots. Modern intensive fruit growing is characterized by the high yielding of trees already in the first years after planting. The greater the volume of the tree crown, the greater the number and total length of shoots on which flower buds can set. The yield potential of fruit trees is correlated with the volume of their crowns and the intensity of flowering ( Treder 2010). Biological factors include the general condition of the trees, their size, and flowering intensity. The most important environmental factors are air temperature and humidity, insolation, and the availability of water and minerals. Yielding of fruit trees depends on many environmental and biological factors. In the assessment of tree growth vigor, a high correlation (r 2 = 0.98) was also obtained between the actual length of shoots measured individually for each tree and the values obtained by analyzing the photographic image, where the MAPE error was 12.9%. Mean absolute percentage error (MAPE) values ranged from 14.0% to 21.8%, depending on the measurement time. Subsequently, the quality of estimating the flowering intensity of pear trees was assessed using a previously determined calibration model. High regression coefficients were obtained between the surface area of petals measured on the photographs and the number of inflorescences counted (r 2 = 0.98) however, observations carried out in the following year indicate the need for individual calibration of estimation models in each evaluation season. Image processing was performed using ImageJ software. Then, a quality assessment of the model was carried out on 26 nonselected trees.
The calibration model for assessing the vigor or flowering of trees by image analysis was based on measurements and photographs taken for nine selected trees differing in the total length of shoots or in the number of flower clusters. The trees were photographed from the same distance using a hand-held camera. Tree vigor was estimated by manually measuring the total length of the central leader and shoots of individual trees.
#Imagej program manual
For assessing flowering intensity, manual counting of flower clusters and taking of photographs of the trees were conducted at full bloom.
#Imagej program software
The study evaluated the possibility of using the image acquisition and processing method with ImageJ software for estimating growth vigor and flowering intensity of ‘Conference’ pear trees.
0 kommentar(er)
