Plant morphology

About: Plant morphology is a research topic. Over the lifetime, 1174 publications have been published within this topic receiving 24418 citations. The topic is also known as: phytomorphology & morphology of higher plants.

Evaluation of chickpea lines/mutants for high growth and yield attributes.

Abstract: A study was undertaken to evaluate the performance of 23 advanced chickpea mutants/lines along with two check varieties Binasola-3 and Binasola-4 at the farmer’s field in Godagari under Rajshahi district during 2006-2007. There was a significant genotypic difference with respect to morphological, physiological, phenological characters, and yield and yield components. Seed yield was positively correlated with plant height, primary and secondary branches, total dry matter (TDM) and number of pods per plant but negatively correlated with days to flowering, days to maturity and protein content. Four mutants/lines viz., CPC-814, CPC-830, CPM-825 (gr) and CPM-834 showed early maturity, higher number of pods and seed yield per plant than all the studied entries, which might be selected for further trials. The highest seed yield (6.93 g plant-1) was recorded in CPC-830. The line CPC-814 produced the highest number of filled pods per plant and the mutant CPM-834 took the shortest days to maturity. Only the mutant CPM-825 (gr) had distinct greenish seed coat color, which could be a genetic marker for identification of developed chickpea genotypes. It was evident that taller plants with higher number of branches and TDM per plant produced higher number of pods per plant as well as seed yield.

Somaclonal variation in plants regenerated from cultures of two morphologically distinct accessions of Aloe vera Linn.

Abstract: Aloe vera (Linn.), an important medicinal plant is cultivated throughout the world. Due to absence of sexual reproduction it lacks genetic variation generated through genetic recombination. The present study was aimed to compare the morphological and biochemical characters of tissue culture derived and field grown clones of two different accessions of Aloe vera with a view to exploit somaclonal variations for plant improvement. The stem disc explants obtained from two morphologically distinct accessions of Aloe vera (HPM1 and PBL3) were cultured on MS medium supplemented with 2, 4 - D (1.0 mg/l) and Kinetin (0.2 mg/l). The callii obtained were sub-cultured on shoot proliferation medium and then on rooting medium. Assessments were made on nearly one year old plants. Plants regenerated by tissue culture techniques exhibited various morphological and biochemical variations. Comparison of somaclones with the parental clones showed variation in size of plants, size of leaves, spines, etc. The callus regenerated plants of HPM1 were bigger in size than the parental clones and showed marginal increase in the amount of carbohydrate, protein, chlorophyll and phenol contents over the control plants. There was decrease in aloin content and juice quantity but increase in gel content in the somaclones. The tissue culture raised plants of PBL3 were smaller in size and exhibited decreased amount of carbohydrate, protein, chlorophyll, aloin, juice and gel contents than the parental clones but have increased amount of phenols. Keywords: Aloe

Modification of plant architecture of Hemidesmus indicus (L.) R. Br. (Iramusu) by in vitro colchicine treatment.

Abstract: The effects of different concentrations of colchicine on shoot and root development of nodal explants and germinating somatic embryos of Hemidesmus indicus (L.)R. Br. (Iramusu) was investigated. MS medium solidified with 8 g/l agar was superior to the liquid medium in all the concentrations of colchicine. In nodal derived H. indicus plants, the highest number of shoots per explant (4.23±1.49) and the longest shoot length (6.36±4.29 cm) were achieved at 5 mg/l colchicines forming a compact bushy type plant architecture. In almost all the treatments an increment of shoot length and number of shoots per explant could be observed compared to the control plants. Furthermore, 1 mg/l colchicine was more effective in germinating somatic embryos to produce more compact plant type under in vitro condition. There was no significant difference observed in different concentrations of colchicine on root length and root number of both nodal derived plants and also in plants derived from germinating somatic embryos. INTRODUCTION Hemidesmus indicus (L.) R. Br. (Iramusu) is one of the wild plant species in Sri Lanka possessing high medicinal value. It belongs to family Asclepiadacea and widely distributed in India, Bangladesh and Sri Lanka. In Sri Lanka, it thrives well only up to an elevation of 2500 m. It is common in deciduous scrubland and deciduous forest of the dry regions as well as rubber, coconut and Pinus plantations (Gunatilleke et al., 2002). The plant is a perennial, semi-shrubby tawnier with a woody rootstock. The stem is very long, prostrate or ascending and slightly twining. Internodes are 1.5 7.2 cm in length. Leaves are simple, opposite and variable from oblong-oval to linear. Flowers are regular, bisexual and contain numerous bracts (Jayaweera, 1982). This plant species can be used as an ornamental foliage plant as well as a medicinal plant, due to its several morphological characteristics such as shape and white color margin along the mid rib of the leaves. Eventhough the medicinal properties of this plant species have been identified and used for many centuries in the ayurvedic, unani and homeopathic medicines (Siddique et al., 2003) at present, not much attention is paid to its conservation in their natural habitats. One of the reasons for less popularity as an ornamental plant is due to its vine like growth habit. Therefore, if it can be modified into a bushy type it will be easy to popularize it as an ornamental potted plant in Sri Lanka. 1 Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka. Nagahatenna and Peiris Chromosomal doubling is a common technique which is used in plant hybridization programmes. It allows induction of polyploid plants possessing superior agronomic traits over their diploid counterparts. Ployploid plants possess larger leaves and flowers, thicker stems and roots, darker green leaves, an increased width-to-length ratio of the leaves, a more compact growth habit and a higher tolerance to environmental stress (Kehr 1996; Kermani et al. 2003; Shao et al. 2003). Furthermore, autotetraploids and triploids are sterile or frequently have low fertility. It is a more important character in clonally propagated ornamental plants since it avoids contamination of the flowers by the pollen and fruit set (Guofeng et al., 2007). Colchicine is one of the pharmaceutically important alkaloids and a useful agent in the treatment of acute attacks of gout. Traditionally, colchicine was used for its antimitotic properties (Sivakumar et al., 2004) and treatment of familial Mediterranean fever. Colchicine has a well-known lipophilic drug action on tumors (Sivakumar et al., 2004). Derivatives of colchicine have shown promise as anticancer agents (Sivakumar et al., 2004). Colchicine was used for gene expression and gene amplification (Sivakumar et al., 2004). Colchicine disrupts mitosis by binding to tubulin, thus inhibiting the formation of microtubules and the polar migration of chromosomes, resulting in a cell with a doubled chromosome number. Now it is one of the most commonly used spindle inhibitors and has been used for the induction of tetraploids from diploid plants of a number of woody species including rose (Roberts et al. 1990; Kermani et al., 2003), mulberry (Chakraborti et al., 1998), rhododendron (Vainola, 2000), pear (Kadota and Niimi, 2002), and pomegranate (Shao et al., 2003). With this information, the main objective of the present study was to obtain genetic variability of H. indicus by colchicine treatment. In this research a reliable protocol is presented for obtaining in vitro cultured H. indicus plants with modified growth habit of bushy appearance. METHODOLOGY Donor plants The nodal explants were taken from plants grown in the plant house, two days after spraying of 0.1% Bavastin (Carbendazim) solution. The nodal explants were surface sterilized by washing 3 times with Teepol, dipped in 0.1% Bavastin solution for 30 minutes, vacuum sterilized with 10% Clorox and two drops of Tween 20 for 5 minutes and thoroughly shake with 10% Clorox for 5 minutes. This was followed by three to four times washing with sterilized distilled water. After the sterilization process 1-2 cm nodal segments were inoculated on Murashige and Skoog (1962) (MS) basal medium supplemented with 1 mg/l 6-benzylaminopurine (BAP) and 0.5 mg/l α-naphthaleneacetic acid (NAA), 3% (w/v) Sucrose, 100 mg/l Myoinositol, 15 mg/l adenine sulphate, 0.1% streptomycin, 0.1 g/l ascorbic acid solidified with 8 g/l agar. Those cultures were incubated at 25±2 C under warm fluorescent light with intensity varying from 900 to 1500 lux and 16 h:8 h (day: night) photoperiod. Shoots were multiplied on MS basal medium supplemented with 2 mg/l BAP (Nagahatenna and Peiris, 2007).

LED Lighting Technique to Control Plant Growth and Morphology

Abstract: Light with diverse spectral distribution can be designed with narrowband lights from light-emitting diodes (LED) in plant factories with artificial lighting. The spectral distribution of the light affects plant growth mainly via photosynthesis, and it affects plant morphology mainly via other light receptor reactions. Photosynthetic reactions and the reactions of light receptors against spectral distribution are described. Plant net photosynthetic rate (Pn) is affected by the amount of light received per plant; hence, plant morphology is important to increase the amount of light received by plants and their growth rates. Plant morphology is affected by spectral distribution via multiple photoreceptors, and it is also affected by photon flux density. Therefore, there may be an interaction between these effects. Understanding these effects and these interactions is required to control plant growth and morphology using LED.