pollen grain


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Related to pollen grain: pollen tube

pollen grain

a small structure of higher plants that contains haploid male gamete NUCLEI and is surrounded by a double wall, the EXINE and INTINE. As the pollen grain ripens in the pollen sac of the ANTHER, the nucleus divides by MITOSIS into two nuclei which have different functions, the ‘generative’ nucleus and the ‘tube’ nucleus (see POLLEN TUBE). Pollen grains are transported from the male stamen to the female stigma in a process called POLLINATION.
References in periodicals archive ?
The yellow passion fruit has floral characteristics such as hercogamy (stylet located above the anthers), the protandry (maturing pollen grains before the stigma is receptive) and a self-incompatibility system (Angel-Coca et al., 2011; Dai & Galloway, Which makes cross-pollination indispensable for fruit and seed production (Yockteng et al., 2011).
To identify the pollen grains adhering to the bodies of the visitors, adhered pollen grains after removing from the body of the visitors with the help of a fine brush, moistened with sterile distilled water, were mounted in 50 % glycerine and observed under a bright-field microscope.
Eight slides were prepared for each collection time, being recorded by the scanning method, under bright field microscopy and magnification of 400x (BEL Fhotonics and Primo Star Zeiss), 250 pollen grains per slide, totaling 2,000 pollen grains per collection time.
Description: Pollen grain, monocolpate, overall amb elongate oval to fusiform, colpus distinct, running entire length of grain with a tendency to become narrow in middle with slightly expanded extremities.
In other species such as tobacco and cabbage, selective destruction of tapetal cells can disrupt the formation of pollen grain and lead to sterility (Cho et al., 2001; Lee et al., 2003).
On average, the genotypes showed high pollen grain viability, ranging from 93 to 98.9% (Table 2 and Figure 1).
Nourmohammadi, "Cytomixis and unreduced pollen grain formation in six Hordeum species," Gene Conservation, vol.
Mann, "Morphosynthesis of complex inorganic forms using pollen grain templates," Chemical Communications, vol.