Editing Ergot (section)

==Life cycle==
An ergot kernel, called a ''sclerotium'', develops when a [[spore]] of fungal species of the genus ''Claviceps'' infects a [[floret]] of flowering grass or cereal. The infection process mimics a [[pollen]] grain growing into an [[Ovary (botany)|ovary]] during [[fertilization]]. Infection requires that the fungal spore have access to the [[Gynoecium|stigma]]; consequently, plants infected by ''Claviceps'' are mainly [[outcrossing]] species with [[Anemophily|open flowers]], such as rye (''[[Secale|Secale cereale]]'') and ryegrasses (genus ''[[Lolium]]''). The proliferating fungal [[mycelium]] then destroys the plant ovary and connects with the [[vascular bundle]] originally intended for [[seed]] nutrition. The first stage of ergot infection manifests itself as a white soft tissue (known as ''[[sphacelia]]'') producing sugary [[Honeydew (secretion)|honeydew]], which often drops out of the infected grass florets. This honeydew contains millions of [[asexual reproduction|asexual]] spores ([[conidia]]), which [[insect]]s disperse to other florets. Later, the sphacelia convert into a hard dry sclerotium inside the husk of the floret. At this stage, [[alkaloid]]s and [[lipid]]s accumulate in the sclerotium.

''Claviceps '' species from tropic and subtropic regions produce macro- and [[microconidia]] in their honeydew. [[Macroconidia]] differ in shape and size between the species, whereas microconidia are rather uniform, oval to globose (5×3 μm). Macroconidia are able to produce secondary conidia. A [[germ tube]] emerges from a macroconidium through the surface of a honeydew drop and a secondary conidium of an oval to pearlike shape is formed, to which the contents of the original macroconidium migrates. Secondary conidia form a white, frost-like surface on honeydew drops and spread via the wind. No such process occurs in ''Claviceps purpurea'', ''Claviceps grohii'', ''Claviceps nigricans'' and ''Claviceps zizaniae'', all from northern temperate regions.

When a mature sclerotium drops to the ground, the fungus remains dormant until proper conditions (such as the onset of spring or a rain period) trigger its fruiting phase. It germinates, forming one or several [[fruiting bodies]] with heads and [[stipe (mycology)|stipes]], variously coloured (resembling a tiny [[mushroom]]). In the head, threadlike [[sexual reproduction|sexual]] spores form, which are ejected simultaneously when suitable grass hosts are flowering.

Ergot infection causes a reduction in the yield and quality of grain and hay, and if livestock eat infected grain or hay it may cause a disease called [[ergotism]]. Black and protruding sclerotia of ''C. purpurea'' are well known. However, many tropical ergots have brown or greyish sclerotia, mimicking the shape of the host seed. For this reason, the infection is often overlooked.

Insects, including flies and moths, carry conidia of ''Claviceps'' species, but it is unknown whether insects play a role in spreading the fungus from infected to healthy plants.<ref name="Butler et al.">{{cite journal |last1=Butler |first1=M. D. |last2=Alderman |first2=S. C. |last3=Hammond |first3=P. C. |last4=Berry |first4=R. E. |title=Association of Insects and Ergot (Claviceps purpurea) in Kentucky Bluegrass Seed Production Fields |journal=Journal of Economic Entomology |date=1 December 2001 |volume=94 |issue=6 |pages=1471–1476 |doi=10.1603/0022-0493-94.6.1471 |pmid=11777051 |s2cid=8725020 |doi-access=free }}</ref>