Agriculture Reference
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The size of the experimental plots is 242 m 2 . The experiment with four replica-
tions was laid out according to the randomized block design. More details of the
experiment are available in earlier reports (Boincean and Nica 2007; Boincean et al.
2013a,b; Boincean 2013b,c).
The long-term field experiment with irrigation, established in 1970, includes six
treatments (alfalfa-alfalfa-alfalfa-winter wheat-sugar beet-corn for grain). The
size of each experimental field is 3 ha. The three systems of fertilization used in
the experiment are without fertilization, composted manure, and composted manure
together with mineral fertilizers. Mineral fertilizers are used for winter wheat (N 60
P 90 K 40 kg a.i./ha) and sugar beet (N 70 P 90 K 60 kg a.i./ha). For sugar beet, composted
manure (80 Mg/ha) is applied each year in crop rotation. The experiment has four
replications. The total size of the experimental plots is 20-400 m 2 , and 50-100 m 2
for measuring crop yields. All plots are irrigated by a sprinkler system at the rate of
water application of 350-400 m 3 /ha. The irrigation water is applied when soil water
field capacity is <75%-80%.
For winter wheat, irrigation is used before and after sowing, and during the veg-
etation period, according the design of the experiment.
For sugar beet, the rates of irrigation are from 300-500 to 800-900 m 3 /ha. The
irrigation is used during three main periods of vegetative growth, taking into consid-
eration the status of soil water field capacity.
Herbicides for weed control have been used only in crop rotations with different
systems of fertilization and irrigation: for winter wheat, Esteron (0.8-1.0 l/ha); for
corn for grain, Trophy 90 EC (2.0-2.5 l/ha); and for sugar beet, Frontier Optime
(1.2-1.4 l/ha). Insecticides used consisted of DecisProfi 250 WG for sugar beets and
Actara 25 WG for winter wheat.
The long-term multifactorial field experiment established in 1996 includes two
crop rotations (with and without a mixture of perennial grasses and leguminous
crops), two systems of soil tillage in crop rotation (combination of moldboard plow
with nonreversible soil tillage and nonreversible system of soil tillage), and three sys-
tems of fertilization (unfertilized, manure, and manure + NPK). Crop rotations vary
in space and time, and have three replications. The experimental layout is random-
ized split blocks. No pesticides or herbicides are used in the experiment. The size of
each experimental plot is 264 m 2 . More details about the experiment are available in
Boincean et al. (2013a) and Boincean (2013b,c).
The 50-year mean annual precipitation is 544.2 mm. However, the distribution of
precipitation is not uniform, especially during the vegetative period. Torrential rains
are received during a short period of May-June in Moldova.
9.3 RESULTS AND DISCUSSION
The industrial model of intensification substantially increased the yields of most
crops in Moldova during the 1970s and 1980s (Table 9.1).
However, yields leveled off or decreased across the country, and also in the Selectia
long-term field experiments, despite the introduction of new varieties and hybrids of
field crops. The yield gap between farmers' yields and experimental station yields
has increased over the last 20 years because of the collapse of the economy. Indeed,
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