Pollen tube the pollen tube responds to extracellular guidance signals to achieve fertilization. Pollen tubes are produced by the male gametophytes of seed plants. They act as conduits to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms. Pollen tubes were first discovered by Giovanni Battista Amici. Pollen tube formation is important for sexual reproduction to occur in seed plants. Plants have separate structures such as microsporocytes and megasporocytes and the pollen grains are transported to the female gametophyte
Spore (agricultural publication) publisher, CTA. Recent Special Issues have covered Climate Change (2015), Family Farming (2014), Structured Grain Trading (2013); Agricultural Value Chains (2012); Modernizing Farms (2011) and Population and Agriculture (2010). Issues from September 1997 (No. 72) to the present are available at the magazine's website . Issues 1-69 are available from . Spore (agricultural publication) Spore is a magazine published by the Technical Centre for Agricultural and Rural Cooperation ACP-EU (CTA) in English and French. It covers a wide range of agricultural topics and is extensively distributed and widely reproduced throughout African, Caribbean and Pacific (ACP) countries and elsewhere. Originally known