In flowering plants, the process of pollen germination and tube growth is required for successful fertilization. A pollen receptor kinase from tomato (Solanum lycopersicum), LePRK2, has been implicated in signaling during pollen germination and tube growth as well as in mediating pollen (tube)-pistil communication. Here we show that reduced expression of LePRK2 affects four aspects of pollen ge...

Mature, self-incompatible stigmas exposed to cycloheximide for 2 h prior to pollination supported identical germination and growth of both cross and self pollen. Treatment of self-pollinated pistils with cycloheximide resulted in the germination of hitherto inactive pollen after some 2-4 h. Pollen germination and initial tube growth in an in vitro germination medium were not significantly affec...

Petunia (Petunia hybrida) pollen requires flavonols (Fl) to germinate. Adding kaempferol to Fl-deficient pollen causes rapid and synchronous germination and tube outgrowth. We exploited this system to identify genes responsive to Fls and to examine the changes in gene expression that occur during the first 0.5 h of pollen germination. We used a subtracted library and differential screening to i...

Pollen of Impatiens sultanii Hook F. germinates and forms tubes rapidly at 25 degrees C in a simple medium containing 111.0 ppm CaCl2, 13.6 ppm KH2PO4, and 1000 ppm boric acid. Calcium, potassium, and boron are essential for germination and tube growth, but sucrose is not required. Pollen tubes grow with equal rapidity in liquid medium or on a medium solidified with 1% agar. Tube growth rates a...

BACKGROUND AND AIMS Silene dioica and S. latifolia experience only limited introgression despite overlapping flowering phenologies, geographical distributions, and some pollinator sharing. Conspecific pollen precedence and other reproductive barriers operating between pollination and seed germination may limit hybridization. This study investigates whether barriers at this stage contribute to r...

Abstract. Avocado pollen was germinated in vitro without recourse to germination on the style. The technique employed involved inclusion of pollen grains in liquid medium of 15% sucrose and minerals and application of 1 or 2 drops on 1% agar plus 15% sucrose and minerals. No germination was obtained on agar plus sucrose without placement of pollen in liquid first. Of the cultivars tested, 'Etti...

The influence of ethylene and CO(2) on pollen germination and tube growth was investigated employing ventilated culture systems. Ethylene had no effect on pollen germinability or tube growth. Germinating pollen did not produce a detectable amount of ethylene (less than 0.1 nl/g.hr). Supplementing the cultures with CO(2) caused a marked increase in germination and tube growth. The half-maximal r...

INTRODUCTION An efficient and reliable method to estimate plant cell viability, especially of pollen, is important for plant breeding research and plant production processes. Pollen quality is determined by classical methods, like staining techniques or in vitro pollen germination, each having disadvantages with respect to reliability, analysis speed, and species dependency. Analysing single ce...

In some plants, pollen grains accumulate storage lipids that serve as energy supply during germination. Here, three enzymes involved in early steps of oil body mobilization in the male gametophyte were functionally characterized for the first time. The effect of extracellular sugars on pollen performance and oil body dynamics was also analysed. Olive pollen oil bodies showed phospholipase A, li...

Air temperatures of greater than 35 ∞ C are frequently encountered in groundnut-growing regions, especially in the semi-arid tropics. Such extreme temperatures are likely to increase in frequency under future predicted climates. High air temperatures result in failure of peg and pod set due to lower pollen viability. The response of pollen germination and pollen tube growth to temperature was q...