resources ( Franco et al., 2001 ; Zhang and Dai, 2010 ). The methods for analysis of genetic diversity in plants were well developed in the last decades, commonly based on the morphological characteristics, seed proteins, isozymes, and DNA markers ( Gepts
Xiao-min Liu, Xin-zhi Zhang, Yi-min Shi, and Dong-qin Tang
Kathryn Homa, William P. Barney, Daniel L. Ward, Christian A. Wyenandt, and James E. Simon
morphological characteristics such as stomata density and leaf curvature influence infection of P. belbahrii in different Ocimum species, and if so, could be effective visual markers for screening in plant breeding. The large morphological variations in the
Ying Gao, Hao Liu, and Dong Pei
)], and hybrid poplar [ Populus alba × ( P. davidiana × P. simonii ) × P. tomentosa ( Dong et al., 2012 )]. Previous attempts have been made to establish the relationships among the morphological characteristics, physiology, and histogenesis of
Sylvia J. Brooks and Paul M. Lyrene
Morphological characteristics of many derivatives from Vaccinium arboreum Marsh × Vaccinium section Cyanococcus crosses were studied. The purpose of the study was to determine if V. arboreum traits were being inherited and expressed in hybrid progeny and to identify characteristics that would enable hybrid field identification. This study focused on the F1 hybrids of V. darrowi Camp × V. arboreum (F1 hybrids) and the open-pollinated progeny of the F1 hybrids [mother is known (MIK)]. Also included in the study were the parents: V. darrowi, V. arboreum, and V. corymbosum L. (pollen parent of the MIKs). Many leaf, flower, and fruit characteristics were measured for all five taxa. Leaf characteristics included length, width, and presence or absence of stalked glands, pubescence, and marginal bump glands. The floral characteristics measured were corolla length and width, corolla aperture, pedicel length, peduncle length, bracteole length and width, and the presence or absence of anther awns and bracteoles. Berry and seed mass were the fruit characteristics investigated. Four unique V. arboreum traits were found to be expressed in the F1 and MIK hybrid populations. These were the presence of anther awns, large seed size, bracteole shape, and marginal glands. These traits should permit field identification of hybrid plants.
I.E. Yates and Darrell Sparks
External “morphological characteristics of catkins from one protogynous (`Stuart') and one protandrous (`Desirable') cultivar of pecan [Carya illinoensis Wangenh.) C. Koch] were examined to define markers of cellular differentiation in the anthers. The angle between the catkin rachis and the bract, visibility of the bracteole, rachis, and anther, and anther color proved to be markers by which development could be categorized into five stages. `Stuart' catkins with bracts as the only externally visible portion of the floret (Stage I) commonly had two locules in each anther lobe. When bracteoles became externally visible (Stage II), cellular specialization had occurred to form a central core containing reproductive cells and tapetal cells differentiated and separated from the exterior layers of the anther wall. Disintegration of tapetal cells and thickening of endothecium eel! walls occurred as the angle between the rachis and bract increased to 45° (Stage III). The anther wall was reduced to only two cell layers, epidermis and endothecium, as the anthers became visible (Stage IV). The pollen grains were mature when the anthers developed a yellowish tinge (Stage V) just before anther dehiscence. Tapetal cells had developed distinguishing traits in anthers of Stage I `Desirable' catkins and endothecial cells of Stage II. Internal anther development was similar for both cultivars from Stages III-V. Trichomes, a common feature-on the surface of the staminate floral parts, became less dense with proximity of the floral parts to the interior of the floret and with catkin maturity.
Natasha Kovacheva, Krasimir Rusanov, Valtcho Jeliazkov (Zheljazkov), and Nedko Nedkov
Bulgaria is famous for its 330-year-old-tradition in rose oil production, which is based on the Kazanluk rose (Rosa damascena Mill. f. trigintipetala Dieck.). The Bulgarian rose oil (otto) is recognized as the ultimate rose oil. For successful selection and breeding work of oil-bearing roses, information is needed on the variation of morphological and phenological characteristics and essential oil composition of locally available genotypes. We estimated the correlation coefficients between yields and morphological characteristics of 15 genotypes of Bulgarian oil-bearing rose. It was found that rose yields depended mostly on the number of flowers, the number of flower branches per bush, and the weight of individual flowers (r = 0.99, 0.88, and 0.84, respectively). Also, we established correlations between the concentrations of various essential oil constituents of the Bulgarian rose oil. Generally, higher concentration of citronellol + nerol was associated with lower concentration of geraniol and stereo-terpens (r = –0.76 and –0.59, respectively). Also, higher concentration of citronellol + nerol was positively correlated to increased concentration of terpene aldehydes (r = 0.63) and esters (r = 0.48). The geraniol concentration was positively correlated to stearoptenes (r = 0.57). Both morphological characteristics and essential oil constituents should be used for further selection of high-yielding cultivars with desirable essential oil composition.
Yan Liu, Hailin Guo, Yi Wang, Jingang Shi, Dandan Li, Zhiyong Wang, and Jianxiu Liu
present study, morphological characteristics and SRAP markers were used to analyze the genetic diversity and relationships among 42 P. vaginatum resources. The variability of certain morphological characteristics and SRAP markers among seashore paspalum
Ed Etxeberria, William M. Miller, and Diann Achor
Fruit etching is an alterative means to label produce. Laser beam-generated pinhole depressions form dot-matrix alphanumerical characters that etch in the required price-look-up information. Pinhole depressions can disrupt the cuticular and epidermal barriers, potentially weakening the natural protection against pathogens. In the present study we describe the anatomical and morphological characteristics of the pinhole depressions in the cuticle/epidermis, and the changes taking place during storage of two fruits: avocado (Persea americana) and tomato (Lycopersicon esculentum). These fruits represent the extremes from a thick, non-edible peel to a thin edible peel. On both tomato and avocado, etching depressions were fairly similar in diameter and depth, averaging 200 μm and 25 μm, respectively, for energy impact durations of 30 μs for tomato and 45 μs for avocado. Immediately after etching, the two- to five-cell-deep depressions contained cuticle/wax deposits. Additional cuticle/wax material was deposited in and around the depressions during storage as demonstrated by confocal, fl uorescent, and light microscopy. In addition, the cells underlining the etch depression increased phenolic and lignin deposits in their walls, creating a potential barrier against pathogenic organisms.
I.E. Yates and Darrell Sparks
Catkin external morphological characteristics of a protogynous (`Stuart') and a protandrous (`Desirable') cultivar of pecan [Carya illinoensis (Wangenh.) C. Koch] were related temporally to the differentiation of microspore and pollen grains. Reproductive cell development was divided into seven periods based on evaluations of number, location, and intensity of staining of the nucleus and/or nucleolus; and vacuolization and staining intensity of the cytoplasm. Catkins with anthers and bracteoles enclosed by bracts did not have reproductive cells that were matured to free microspore. Free microspore developed only after bracteoles became externally visible. The Period 1 nucleus was at the periphery of the cell and a large central vacuole was present; at Period 2, the nucleus was at the center and vacuolation had been reduced. As the angle between the bract and catkin rachis increased to 45°, vacnolation was reduced as the nucleus enlarged and moved to a central location in the microspore (Periods 3 and 4). The majority of the pollen grains were binucleate, and the generative nucleus became elliptical (Periods 5 and 6) by the time anthers became externally visible. Acetocarmine staining intensity of cellular components masked the presence of the generative nucleus (Period 7) just before anther dehiscence. Staining reaction for protein was positive from Period 1; starch from Period 3; lipids and polyphenols from Period 5. The mature pollen grain was abundant in stored reserves of starch and lipids and had a wall with a thicker exine than intine as demonstrated by acetolysis.
Yun Kong, Xiangyue Kong, and Youbin Zheng
modeling. Table 1. Descriptive statistics of the measured variables used to derive and validate the models for estimating fresh weight of pea shoots. Correlation coefficients for FW and measurable morphological characteristics of pea shoots sampled for