BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Improving uniformity of potato crops - Simon Smart
DTSTART:20140228T133000Z
DTEND:20140228T135500Z
UID:TALK50434@talks.cam.ac.uk
CONTACT:Megan Cooper
DESCRIPTION:Approximately 10% of the yield of potato crops is wasted as tu
 bers are too small or too large to be marketable. The yield and number of 
 tubers in a crop determine the mean tuber size and the mechanisms controll
 ing these are well understood. Irregular irrigation and infection of the c
 rop by Rhizoctonia solani are known to increase variability in tuber size\
 , but the fundamental causes of variation in tuber size are poorly underst
 ood. Plant-to-plant variation in yield\, stem number and tuber number has 
 long been noted to occur in potato crops and we are seeking to establish w
 hat influences this variation and whether it has any influence on variatio
 n in tuber size of the crop.\nSurvey work has been performed where individ
 ual plant growth was studied in detail\, including the first study of the 
 growth of individual stems in the field. We found that higher yielding ste
 ms produced larger tubers\, as tuber number does not increase in proportio
 n to yield\, and thus reducing variation in stem yields would decrease var
 iation in tuber size. Field experiments were conducted where variation in 
 seed tuber weight\, date of emergence and within-row spacing were altered.
  None of the treatments caused significant differences in the variation of
  tuber size\, plant yields or above-ground stem weights. Regression analys
 is revealed that variation in the date of emergence was the primary cause 
 of variation in plant yields\, but seed tuber weight also had a small infl
 uence. Non-destructive measurements of plants early in the season showed t
 hat the hierarchy of plant size persisted to the end of the season\, but w
 as also affected by neighbouring plants. Where variation in within-row spa
 cing was altered\, plant yields did not correlate with the space per plant
 . Variation in stem yields was influenced by stem number per plant and the
  date of emergence\, but we also propose that variation in the amount of s
 eed tuber substrate per stem is important in determining their initial rel
 ative size and ultimately the size of tubers that they produce. \nFurther 
 work will examine how variation in seed tuber weight\, date of emergence a
 nd within-row spacing interact with each other in Maris Piper\, survey pla
 nt-to-plant variability in other varieties and establish how other varieti
 es respond to variable within-row spacing.\n
LOCATION:Department of Plant Sciences\, Large Lecture Theatre
END:VEVENT
END:VCALENDAR