Agriculture Reference
In-Depth Information
Integrated Plant Management and Plant Hygiene
Optimal climatic conditions under protected cultivation are not only favorable for
growing crops, but also for the development of pests and diseases. Therefore, in-
tegrated plant management and plant hygiene in greenhouses are of utmost impor-
tance. Generally, plant protection in greenhouses is applied according to the prin-
ciples of the integrated pest management or organic production principles. Both
these methods aim to reduce pest and disease incidences in greenhouses crops due
to a minimal use of pesticides or application of alternative methods to control pest
and diseases, respectively. Moreover, both these methods are oriented towards an
adaption of sustainable greenhouse production.
The Interaction of Factors, their Multiplicity and Effects
on Plant Growth and Development
Many specific environmental and agronomic factors influence plant growth, yield
and product quality of protected crops. Only when all these factors are in optimal
level, in balance, and well managed and sustainable can it be expected that plant
growth and development will be at its best. Liebig's Law of the Minimum, states
that growth is controlled not by the total amount of resources available, but by the
scarcest resource available (limiting factor). Optimum growth and performance will
be a function of the genotype used, with the developmental and maturity stages, and
a function of interaction between all environmental conditions and agronomical
measures. Furthermore, according to Raviv et al. (
2008
), when multiple factors are
limiting, the interacting effects are more complex than simply suggesting causality
of suboptimal production to the most-limiting factor. This is particularly important
in practice because it is extremely rare that all production factors can be simultane-
ously optimized in a living system.
Increased light intensity leads to an increase of the photosynthesis rate until
light saturation level. However, under high CO
2
concentrations, light saturation
may shift to higher light levels. Similarly, optimum temperature of the net photo-
synthesis rate can increase by increasing light intensity. Optimum temperature of
net photosynthetic rate is also affected by CO
2
-concentration. Similarly knowledge
of greenhouse design and the technology are associated with effective crop man-
agement. Singular actions such as these are extended into complex questions of
entire measures, in order to improve the sustainability of such systems. Based on
advanced sensors and robotics, it is possible to involve all environmental factors
in greenhouse climate control. Sustained efforts to balance the greenhouse climate
conditions with other factors such as outside conditions, weather forecasts, light and
energy efficiency, water and fertilizer use efficiency must be undertaken. In turn,
these factors could be integrated together with crop management and plant growth
rate to optimize the greenhouse utilization.
