Phytophthora pathogens are responsible for some of the most serious diseases of cocoa including phytophthora pod rot (PPR) or black pod, stem canker, leaf and seedling blight, chupon wilt and flower cushion infections. PPR causes 10–30% annual losses in production of cocoa beans globally, and much higher losses locally in particularly wet and humid conditions. Stem canker causes further losses ...

The phytopathogenic fungi Phytophthora subspecies elicit hypersensitive-like necroses on their nonhost tobacco (Nicotiana tabacum), with the exception of the tobacco pathogen Phytophthora nicotianae. In culture, these fungi-except P. nicotianae-secrete proteins, called elicitins, that cause these remote leaf necroses and are responsible for the incompatible reaction. These proteins protect toba...

The evolutionary history of Phytophthora cryptogea and P. drechsleri isolates previously collected from floriculture crops in North Carolina commercial greenhouses was explored with coalescent- and parsimony-based analyses. Initially, 68 isolates representing 13 location-host groups were sequenced at multiple loci. Sequences of all isolates within a group were identical. A subset of isolates we...

Let $H$, $L$ and $X$ be subgroups of a finite group$G$. Then $H$ is said to be $X$-permutable with $L$ if for some$xin X$ we have $AL^{x}=L^{x}A$. We say that $H$ is emph{$X$-quasipermutable } (emph{$X_{S}$-quasipermutable}, respectively) in $G$ provided $G$ has a subgroup$B$ such that $G=N_{G}(H)B$ and $H$ $X$-permutes with $B$ and with all subgroups (with all Sylowsubgroups, respectively) $...

let $g$ be a finite $p$-soluble group‎, ‎and $p$ a sylow $p$-subgroup of $g$‎. ‎it is proved‎ ‎that if all elements of $p$ of order $p$ (or of order ${}leq 4$ for $p=2$) are‎ ‎contained in the $k$-th term of the upper central series of $p$‎, ‎then the $p$-length of‎ ‎$g$ is at most $2m+1$‎, ‎where $m$ is the greatest integer such that‎ ‎$p^m-p^{m-1}leq k$‎, ‎and the exponent of the image of $p$...